Originally posted by Yakumo_2020:

I just figured out how to prevent Steam from updating Valheim unless I want it to. I was able to get a backup of Valheim version .209.10 working again and Steam can't update it.

tl:dr : I changed ownership of the Valheim folders so the Steam client running as a non privileged user can not delete, change, replace any files in the Valheim folder. The save files are in a dirrecnt directory and unaffected.

Sadly this does not fix the curent issues with the last 2 updates unless you happen to have a backup of the Valheim folder from before things went FUBAR. (you do make backups of the game folders before installing mods right?)

This is a Linux solution. I don't know if this is even possible with the newer versions of Windows. Last ver I worked with was 7

The games version will remain locked until ownership of the files is changed back to original settings

Note that this will cause issues connecting to servers running newer versions of the game.

details for the fellow techies :D
As root in the

~/.steam/debian-installation/steamapps/common

directory I used

'/bin/chown -R root:staff Valheim'

to recursivly change the ownership all files in the Valheim directory to owner:root and group:staff. This ownership:group setting allows non root users to execute the game files but not change them.

EDIT
I realized recently that Just setting the files to read only would probably work too, and is a possible solution in a Windows environment

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Dunno if you fixed it yet but here's my solution and it's fixed Valheim *twice* now that it's crashed with updates.

Use the latest Glorious Eggroll as your Proton version whenever Valheim updates. It's worth a try and both time I had screen crashing that wouldn't let me in the game, GE fixed it with no hassles (and I had tried every fix I could find for days)

Save your worlds/chars in a file on your desktop or wherever and sometimes one or the other will load back in.

Hope that helps. Dunno about servers but this may work for those who solo play.