I did nothing. Everything was ok and working fine but somehow, I tried to start GTA V and this happened:
I tried those:
-Verified game files via Steam. (Didn't work)
-Tried to delete mods folder. (Worked)
But I don't want to re-install everything. Is there any solution? I searched error name but nah, nothing helpful.
Game Version: 1.0.1868.0
Have a look in your 'OpenIV.log' (in GTAV root folder. Check other '.log's for info too) & see if you can track down exactly what '.rpf', or file inside it, is causing the 'ERR_FIL_PACK_3' then either, replace that file (might work), or rebuild the entire archive manually using a working vanilla '.rpf' from the game folder.
You can open the broken '.rpf' & move it's pertinent (ie modded) files to a folder in windows & use those files to rebuild the new one.
It won't take long to do it that way
you may have to update both your update.rpf and you can find simple solutions using OPENIV patch OIV installation solutions to get a better result out of your update.rpf being out of date and not being verified properly that way you dont lose out on your mods.
hopefully you found some luck shoot me a message if you ever need more questions answered had tons of these errors before and most of them were mods matching the update.rpf to the game directory folder and so on.