Failed to parse addon file

[Schroedi77]

IS there a way to fix it?And if yes then please tell me

[Exotetere]

As far as I know (from experience), this is an issue with the mod itself and has to be manually fixed by the addon creator.

[AgentUsa228Pork]

I found a solution to this issue, at least I succeeded, I tried a lot, reinstalled the game, deleted files and did other unnecessary and non-working nonsense. NOW I WILL TELL YOU HOW TO DO IT.
Steam settings - disk space - add a disk, select a new disk there, and now, when installing the game, select your new disk, download Gmod there and your add-ons should to work.

[JaseMcDougal]

@agentusa228pork already tried deleting the files AND using another disk, didnt work either time :\