@Alaannnn
What actual error do you get when is says corrupt game? There are a few 'ERR_FIL_PACK_3', 'ERR_GEN_INVALID' etc. Also, any '.log' files? If so, copy them to Pastebin & post the link/s here. Thanks
Do ALL add-ons cause this error or just some? List the ones that do & the ones that don't if you can. Link to the ones that break it if you can as that would be ideal
If you can provide screenshots of your 'Grand Theft Auto V' main folder & 'scripts' folder (if you have one) that may help too.
Also, any other info that might be relevant to your game being different to the average install. Installed on external drive - copying 'mods' folder from old install - Just "upgraded" (sold soul ) to Windows 10 etc.
Are you redownloading ALL the mods you are trying to install each time you try to install them or installing them from the same files/location on your computer?
What version of the game are you running? Was it the same as you ran before (when it worked) or have you updated as you reinstalled etc.
Got to cover the basics here, sorry.
What modded 'gameconfig.xml' are you using?
Also, have you installed OpenIV's 'ASI Loader' & 'OpenIV ASI' plugins (OpenIV > 'Tools' tab > 'ASI Manager') before installing any (esp. '.oiv') mods? It should look like this:
Just double-check & confirm both of them ('openCamera' not important) are installed correctly. Uninstall & reinstall them too even if they are just in case
If you reinstall again, reinstall to a new folder location (in case of corrupt Windows registry etc). Maybe run CCleaner's Registry Cleaner once you uninstall but before reinstall. Don't worry, it's not like all other 'Registry Cleaners' that dig too deep. I've used it for 10+ years multiple times a week without a single error/problem.
Once it completes the scan & you 'Fix all selected issues' (backup registry if you want to feel safe. Option will appear), run it a second time to clean any leftovers.
Depending on what version (Steam, disc etc) of the game you are using you might want to look at verifying that your vanilla install is 100% fine (ie not corrupted etc).
I have more ideas but that's probably enough to get you started. Let me know how you get on & we'll take it from there