A corrupt file in the Rocket League Cache is the most common culprit of these error messages. Deleting the cache typically fixes this error.

1. Click on the Folder Icon in the lower left corner of the screen
   This will open File Explorer
2. Click on Documents in the left-hand column
3. Double click on My Games
4. Double click on Rocket League
5. Double click on TAGame
6. Right click on Cache
7. Select Delete

Try starting Rocket League again

If Rocket League still won't start, try renaming the Rocket League folder:

1. Click on the Folder Icon in the lower left corner of the screen
   This will open File Explorer
2. Click on Documents in the left-hand column
3. Double click on My Games
4. Right click on Rocket League
5. Select Rename
6. Type Rocket League Old
7. Tap the Enter Key on your keyboard

Try starting Rocket League again