This will set everything back to playable, Seven easy steps to follow that work perfectly to restore the game.

Please do not ignore any step as that one missed step may be the item needed to correct your error. For mod users this guide sets a "ready" state for your playsets to be re applied for you to then start troubleshooting the mod that caused the crash, failure or error.

>>>>> But first, before you do anything make sure you purge your root drive of any CS2 save files copies or directories that you may have created in the past. Be sure there are no other Steam profiles on your computer that may have left any saves anywhere on the root drive as saves left in another profile if corrupt will halt loading any profile as the game verifies every save on the root drive.<<<<<<
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All this fix does is reset your game settings and allow the game to start and run.
Please follow every step in order and do not modify or omit any. Each step is designed to correct specific known errors, miss one and it still crashes start over and do the whole procedure in order again.

The fix will require you to find and manipulate the AppData folder in Windows.
The AppData folder is a hidden folder within your user profile where Windows stores application-specific data, settings, and files.

To unhide this folder in Windows open File Explorer from the taskbar;
Select View. Go to Options and select Change folder and search options.
Select the View tab. In Advanced settings, select Show hidden files, folders, and drives.
Select OK. All hidden files and folders are now visible.

Most players will then find the CS2 AppData folder here;
C:\Users\(your user name or number here)\AppData\LocalLow\Colossal Order\Cities Skylines II
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Now ttart the CS2 refresh;

STEP 1 - Second to mods the biggest source of crashes and errors is CORUPT SAVE FILES.
MOVE (not copy) the entire "Saves" folder to a drive other than "C"
This first instruction requires to "Move" the entire save folder OFF of C "drive".
Some crashes and mod irregularities can be caused by corrupt Autosave files.
It may be good to delete all the old Auto Save files before moving the folder.
If you had a corrupt save this alone might correct an error but will happen again if you put the corrupt save back. So do the entire process at least once.

Alternatively you can just delete the "Saves" folder completely if you don't care about past saves. If you want to preserve old saves do not simply copy them elsewhere as that command will change files dates to the time of copy (right click, select move)

STEP 2 - Now Delete ALL the other folders and files left within the Cities Skylines II folder.

STEP 3 - DO NOT delete any other folders from AppData other the ones instructed that are ONLY within the CS2 folder.

STEP 4 - Login to PDX Mods and temporarily disable all mods and playsets (if any)
https://mods.paradoxplaza.com/games/cities_skylines_2?orderBy=desc&sortBy=best&time=month

STEP 5 - Ensure Steam Cloud Sync is "Off"
https://cs2bus.com/steamhelp/en/faqs/view/68D2-35AB-09A9-7678

STEP 6 - Now do the "Steam verify files" thing and restart With "Code Mods Disabled"
https://cs2bus.com/steamhelp/en/faqs/view/0C48-FCBD-DA71-93EB

STEP 7 - Important! Start a new map and do a quick save and restart again with Code Mods Disabled before restoring your saves folder back to where it was.

This will get you back and running for sure if you have any old mod, save or custom asset causing the failures.

However, it may come back again in future as you enable mods or custom assets, just do it again if you need. It is easy and no harm to anything.

For a satisfactory outcome Please try to follow these instructions exactly as written.
Each step should be done exactly as directed at least the first time.

Thank you to all who contributed and tested this ongoing community effort.

Good luck! Enjoy!
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