Section last checked: Apr 2019
This guide focuses on problems that can affect all users, regardless of operating system.

As a starting point, always unsubscribe from known broken mods[docs.google.com].

We recommend all users subscribe and enable the excellent Loading Screen Mod - it drastically reduces load times, massively reduces RAM consumption, and has significantly better error reporting.

If you haven't already done so, try they guide specific to your operating system first:

• Windows Troubleshooting Guide
  
• Mac Troubleshooting Guide
  
• Linux Troubleshooting Guide
  
• Performance Tuning Guide

You can use Ctrl+F to search this guide (Mac users: Cmd+F). Try manual browse if search fails.

The contents of this guide are ordered from start to finish as follows: Launching the app > Main menu & Content Manager > Starting/Loading a game > In-game > Exiting Game.

If you have a problem that's not solved by these guides, best thing to do is ask in the discussion forums. You can also get tech support via the official C:SL Discord chat server[discord.gg].

You can refer people to this guide by copying this URL.

If you're having problems setting up transport routes, powerlines, making tunnels, etc., there are some sections later in this guide that provide solutions. Also, you can view or download the game manual.

Section last checked: Apr 2019
Change your Steam Download Region, then Refresh Steam Files and finally Verify Game Cache. Wait until everything has finished, then reboot your computer and try again.

Also, check to see if you have any incompatible virus protection, firewall, proxy server, parental controls, etc. Easiest way to do this is to google "Steam" and then the name of software that you think might be conflicting.

Section last checked: Apr 2019
You might also see an error like "Either you don't own the game or Steam is broken beyond repair".

Completely log out of Steam, then log back in again.

Still not working? Change your Steam Download Region, then Refresh Steam Files and finally Verify Game Cache. Wait until everything has finished, then reboot your computer and try again.

Section last checked: Apr 2019
Unsubscribe from the following mods:

• Improved Assets Panel
  
• Improved Mods Panel

Section last checked: Apr 2019
If your laptop only has a low power graphics card (usually made by Intel) you probably don't meet the minimum system requirements to run the game (see Appendix B at bottom of this guide).

If your laptop has a good graphics card (Nvidia, ATI, etc), the game will sometimes use the low power graphics card by mistake. Here's how to fix that[www.howtogeek.com].

Mac user? Try the gfxCardStatus app[gfx.io].

Section last checked: Apr 2019
First, try the More Aspect Ratios mod.

Still not working? Try Launch Options to set screen size.

Section last checked: Apr 2019
See this guide[github.com]. There are several related guides - click here[github.com].

Section last checked: Apr 2019

If the Load menu item is working but the New Game menu item is disabled...

You need at least one map to be available in order to start a new game. Did you disable or delete all the maps from Content Manager? If so, either enable a map or subscribe to a map from Steam Workshop and then restart the game.


Do you have any save games? If not, you can't load one, Duh! :P


Make sure /home/user/.config is writeable.

Also, disabling second monitor will sometimes bring the New Game button back.


Easy fix: Close steam and run it as Administrator.

Better fix: Make sure the following folder has read and write permissions for your user:

• Launch Finder.
  
• Menu: Go > Go to folder. Enter ~/.config/
  
• Select .config and press ⌘-I to open folder properties
  
• In sharing and permission change all access from Read to Read and Write.
  
• Next time you run the game it should create a folder called "Colossal Order" in the .config folder – if it doesn't, you've not set the permissions properly

If that doesn't solve it, try this:

• Click on Macintosh HD then right click on your user name and select Get Info
  
• Unlock the lock at the bottom of the popup and put in your password
  
• Press the "+" (plus/add) button at the bottom left in Sharing and Permissions
  
• Add "Administrator" to the list and set as "Read and Write"

If that doesn't solve it, are you running a custom resolution due to launch parameters (see Appendix A at bottom of this guide)? If so, try different resolution or remove those parameters.

Section last checked: Apr 2019
Things to try:

• Which operating system user account were you logged in to when the saves were made? Check you're logged in to that account.
  
• Which Steam account were you logged in to when the saves were made? Check you are logged in to that account.
  
• From the game main menu, choose Content Manager > Savegames and ensure they are enabled.
  
• Nothing in Content Manager? Try these guides[github.com].

Section last checked: Apr 2019
Check to see if they are listed in Content Manager.

If a save is broken, it will have either a red file name or a broken/empty image preview. Deleting broken saves (take a backup first if you want) might help.

Save game folders are listed in Appendix E at the bottom of this guide.

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If you see this for a very long time (more than 2 minutes) when loading a game or starting a new game...



Unsubscribe the following mods:

• Auto Line Color
  
• City Web Server
  
• Any mods marked as broken on this list[docs.google.com]

A recommendation for all users is to subscribe and install the excellent Loading Screen Mod - it's much faster loading, greatly reduces RAM consumption and is significantly better at logging errors during the loading process.

Mac users: See Mac Troubleshooting Guide for some additional causes of this bug.

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If you see something like this (particularly if your roads are all grey and broken)...



...it's usually caused by unsubscribing workshop vehicle assets (this mod can help fix that), in particular those associated with public transport such as buses and trains or services such as police and garbage. It can also be caused, to a lesser extent, by unsubscribing building assets.

Note: Even if you didn't unsubscribe, the asset might have been removed from the workshop (eg. due to copyright infringement, which happened with a few car assets).

Mod (code) authors: This error will affect your mods, making the error messages appear to come from your mods when in fact it's something from core game. Some details here as to things you can do to mitigate the impact the error has on your mod.


Note: It's likely that the bug with this mod was fixed on 15th June 2015.

If you're using the No Despawn Mod, unsubscribe it to see if that helps.


If this works, you can delete the routes to cause those assets to despawn and then make a new save that doesn't contain them. There is no way from the log files to determine which assets are missing, so you just have to do trial and error.

Tip: See the "Loading/Starting a Game" section in this guide which lists variants of the "Object reference not set to an instance of an object" error along with suggestions of what type of asset would have caused it. This can help you work out more quickly which assets to resubscribe to.

Tip: You can use the Advanced Vehicle Options mod to prevent unwanted vehicle assets from spawning.


Note: We've had several confirmations that this method will solve the error or at least improve the situation (thanks peter.geri2, grapplehoeker and everyone else who provided feedback!), but we aren't sure what side effects it could cause so take a backup first.

• Make sure you have a gamesave
  
• Note down the mods you have running
  
• Make sure you know your Paradox account info
  
• From the main menu in C:S, choose Options > Misc > Reset configuration
  
• Start a new city then exit that city
  
• Re-enable all your old mods
  
• Load your old gamesave

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Unsubscribe the Alternative Siren Sound mod and run a virus scan and malware scan (the mod is a phishing attack that affects Windows users).

Note: As the mod is no longer in the Workshop you'll have to remove it via Content Manager or alternatively delete it directly from disk (it will be in the 418216826 folder).

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• Text too small? Get bigger text, custom fonts
  
• Blurry UI? Use Silicon Skin for clean, crisp interface text and graphics.
  
• Color blindness? change zone colours
  
• Map area too blurry around the edges? Reduce "tilt shift" setting in Game Options screen.

Section last checked: Apr 2019
Check that Shadows are enabled in Game Options screen.

Windows users: Try the -force-d3d9 Launch Option to force DirectX 9 mode.

THIS SECTION NEEDS UPDATING

If you see something like this lurking under the map (eg. it appears when terraforming or when first person view in a tunnel, or with certain camera mods, etc)...



...that thing is the famed phantom bridge of C:S.

It's currently believed to be a side-effect of using the "Some Roads" mod.

Note: It's NOT caused by Traffic++, that bug was squished[github.com] some time ago[imgur.com].

THIS SECTION NEEDS UPDATING

There are several sounds in the game that people dislike, the quickest way to deal with it is using this mod:

http://steamproxy.net/sharedfiles/filedetails/?id=455958878
Tip: The "bip bip bip beep bip..." sound is from the commercial district (it's merged in to the main sound file so you can't remove it on its own, you have to turn down the volume for whole commercial zone).

You can instantly change the siren sound of emergency vehicles, and even use your own custom sound (.ogg format), using this mod:

Note: The police and ambulance are hard-coded in game to use same sound file :(

http://steamproxy.net/sharedfiles/filedetails/?id=435167188

The Alternate Siren Sound (American siren) was making connectiosn to external site. If you were using that mod on Windows do a full virus and malware scan.

As the mod is no longer in the workshop the only way to delete it (if you still have it installed) is via the Content Manager or by finding it's folder on disk (the folder will be called 418216826).


Currently no way to change volume of the chirper, but you can use this mod to eradicate it completely:

http://steamproxy.net/sharedfiles/filedetails/?id=405791507

Currently no way to change volume of seagulls, but you can eradicate them with this mod:

http://steamproxy.net/sharedfiles/filedetails/?id=421041154

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If there is a subway going under a road, vehicles will sometimes stop and wait until the subway train has passed (known bug). Move the subway or the road to a new location to prevent this happening.

Also, there have been some reports of Traffic++ causing this problem: Disable "Realistic Speeds" option in mod settings.

Section last checked: Apr 2019
See these guides[github.com].

THIS SECTION NEEDS UPDATING

If you've subscribed an asset but it's not appearing in game (just that specific asset - other subscribed assets work fine) look for this error in your Player.log (Mac / Linux) or output_log.txt (Windows)...


If you find it, the chances are the asset is broken. The most common cause for this is that the asset author had a mod installed that changed the assets AI class in the asset editor. In most cases the asset author will be completley unaware of this problem - they have the mod so they won't see the error messages.

The only way to fix the problem is to change the AI class of the asset – this is something the asset's author needs to do; please point them to the V10DeleteAI mod which can help them make the required changes.

Section last checked: April 2019
Use Advanced Vehicle Options (AVO)[http//Advanced+Vehicle+Options+%28AVO%29] mod (that link is for new version) to control which vehicles spawn. There is a guide explaining how it works (note: the guide points to old version of the AVO mod, use the new link above).

Additional control can be achieved by using mods such as Service Vehicle Selector (for service vehicles) and Improved Public Transport 2 (for transport vehicles).

Section last checked: April 2019
Go in to the Roads menu and click the small Road Upgrade button, then right-click any one-way road to change it's direction.

To make a one-way road 2-way, or vice versa, select the type of road you want and then with the upgrade tool active click on the road on the map that you want to change.

You can do the same with train tracks, pedestrian paths, fences, etc.

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Make sure you're not subscribed to Steeper Slopes mod (it's no longer in workshop but you can unsubscribe from Content Manager > Mods screen in C:S).

For other potential causes and their solutions, see "Tunnels aren't working?" section in 1.1.0b Patch Troubleshooting Guide.

To make underground powerlines, press PageDown while placing them (Mac users: Fn+Down arrow).

Thanks to /u/whisperproud for this tip!

Some maps don't have flowing rivers (no arrows on the water) on purpose to provide additional challenge. So how do you keep sewage and drinking water separate?

Use water towers for your drinking water, and be careful where you dump sewage. Also make sure your water towers aren't on polluted land, otherwise your cims will get sick.

Thanks to Phoenix C64 for the tip!

Section last checked: April 2019
Things to check:

• Make sure water pumps are not in or near polluted water
  
• Make sure water towers are not on or near polluted land
  
• Make sure you have a sewage outlet to get rid of dirty water
  
• Make sure you have sufficient health care coverage

There's also a video explaining how pollution works.

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You need at least 1 bus depot before you can create bus routes.

If you have a depot but still can't make bus routes, try using a different bus depot asset. (Asset authors: Republish your assets from the Asset Editor in C:S 1.1.0 or above and it will start working properly.)

• Draw a route by left-clicking next to roads to create one or more stops.
  
• ...The route must join at both ends.
  
• Delete an existing stop by right-clicking its circle.
  
• Move an existing stop by dragging it's circle to a new location.
  
• Add new stops to an existing route by dragging the route line to the side of a road where you want the new stop to be.
  
• To delete an entire line, delete all the stops on it, or click on a bus and "Modify Line" then "Delete Line".

You need at least 2 metro stations (otherwise people will go underground and never be seen again lol).

If you have metro stations but can't draw metro tunnel or metro routes, try using a different metro station asset. (Asset authors: Republish your assets from the Asset Editor in C:S 1.1.0 or above and it will start working properly.)

Draw metro tunnel between the stations so there is a path for metro trains.

Draw a metro route between the two stations, making sure the route joins at both ends.

You can delete, move or add stops in the same way as you do for buses. In underground view, you can click on a metro train and Modify Line to change colour, rename, delete, etc.

Avoid having more than two routes through the same station platform, it can cause metro jams!


You need at least one passenger rail station to receive tourists.

You need at least two passenger rail stations before you can set up routes within your city.

If you have train stations but can't draw passenger train routes, try using a different passenger station asset. (Asset authors: Republish your assets from the Asset Editor in C:S 1.1.0 or above and it will start working properly.)

Draw a route between two passenger stations to set up local rail service between those stations. The route must connect at both ends.

Cargo stations are a bit easier to set up: Just connect them to the external rail network and resources/goods will be automatically imported/exported. You can also transport goods locally by having cargo stations on the same track.

THIS SECTION NEEDS UPDATING

Make sure your map has a shiping connection; you can see what connections a map has on the screen when you are starting a new game.

Note: The popular Copper Creek map doesn't have a shipping connection.

To build a harbour or docks you'll need to own an area on the map that has acces to a shipping lane; when buying areas (after reaching milestones) hover over an area and it will tell you what features are available in that area. You'll need an area that's very close to the shipping lane before you can place a harbor/dock.

Thanks to grapplehoeker for the tips.

If you see something like this...



...it's caused by using "Overlap" mode feature of mods like NoPillars or Road Anarchy; luckily it's easy to fix!

Go to the affected area and make sure the mod is running in "Collision" mode then upgrade a road or plop a small park or some other building nearby. This will force a reset of any nearby zoned areas, and zones that are colliding with roads will be removed (causing any buildings on them to despawn).

There might be some trees and stuff left over but those can be removed using the bulldozer tool.

Note: The mods are safe to use and give far greater flexibility when constructing things, just be sure to always switch back to collide mode and upgrade or place something nearby to make sure the stuff you built is properly deteced by the game engine.

THIS SECTION NEEDS UPDATING

If you see something like this...



...did you install a mod in the wrong folder? It's best to subscribe to mods via Steam workshop rather than manually install them.

THIS SECTION NEEDS UPDATING

The following mods are known to cause this:

• Help Button Remover
  
• Traffic Manager (may have been fixed since time of writing this)

You can either disable them before using asset editor, or unsubscribe them.

Note to mod authors: Check LoadMode or AppMode[www.skylineswiki.com] before initialising your mod if you want to prevent it from being used in asset editor.

THIS SECTION NEEDS UPDATING

Turn off FXAA in the Nvidia control panel.


If you've installed lots of assets from the workshop, that will sometimes cause crash on exit.

You can quickly test by using the --noWorkshop Launch Parameter temporarily disable all assets.

See also the Performance Tuning Guide which has some other suggestions regarding workshop assets.

Last checked: August 2019

http://steamproxy.net/sharedfiles/filedetails/?id=466981085

Section checked: August 2019

The game is resource intensive. Despite what the game requirements state, you need at least 8GB RAM, ideally 16GB. A fast CPU primary core (ideally 3.8GHz or faster) is the main factor in terms of game performance. Most modern graphics cards should work fine.

Note: Just because you can run other similar games, for example Cities in Motion, Sim City 4, or Cities XL, doesn't mean that Cities:Skylines will run. This game is far more resource intensive than most other games you've played, and due to limitations of the Unity engine it is massively dependent on the primary CPU core.

For much more detailed info, see:
https://steamproxy.net/sharedfiles/filedetails/?id=465790009
That guide also details how many assets/mods you can likely use depending on your system specs.

Tip: If you are a Windows user, you can use System Requirements Lab[www.systemrequirementslab.com] to find out if your hardware can run the game.

Last checked: August 2019

http://steamproxy.net/sharedfiles/filedetails/?id=463645931

See "Problem not solved?" section at end of this guide.

Section last checked: August 2019

Tip: Deleting unwanted save games will make the game load faster!








Go to the Library tab in Steam, and right-click the game name. Go to the Local Files tab and select "Browse Local Files". Look for the following folder (the <steamid> is a big long number):

Last checked: August 2019

Before doing a reinstall, Refresh your Steam files and see if that solves the problem.

Note that Steam will automatically re-download all your subscribed mods and assets. If you don't want to do that, go to Workshop tab above, then hover "Your files" in sidebar and choose "Subscribed items" - you'll get a list of all your subscriptions and can unsubscribe them individually, or click the "Unsubscribe all" button in the sidebar.

• Remove the game from Steam (delete local content)
  
• Delete all these files and folders:
  
  • ...\Steam\steamapps\common\Cities_Skylines\
    
  • ...\Steam\userdata\<SteamID>\255710\
    
  • ...\Users\<UserName>\Documents\Colossal Order\Cities_Skylines
    
  • Note: For these last two, move their /saves/ folders elsewhere first to keep your save games...
    
  • ...\AppData\Local\Colossal Order\Cities_Skylines
    
  • ...\AppData\Roaming\Colossal Order\Cities_Skylines
• ...then reinstall the game via Steam.

Drag the app in to trash, empty trash, then reinstall via Steam client.


?

Last checked: August 2019

You can get official tech support via the official C:SL Discord chat server[discord.gg] or Paradox support forums[forum.paradoxplaza.com].

You can often get help from other users in the main Steam discussion forum. Also, the developers of TM:PE mod have compiled a useful Troubleshooting Guide[github.com] that might help (it's not just for TM:PE, most of the issues are caused by other mods, assets, game bugs, or just common mistakes made by users).
.