I just downloaded and installed the game this afternoon. I haven't even created a character. What does this message mean? (and yes, I did a verify/repair before posting).

basically it means your install has an issue

did you use Galaxy or off line?
is it installed to c program files?
is the deluxe dlc installed?

have you got a Larian account... when you fire up the Larian launcher does it have a little green dot next to 'MY ACCOUNT" in the top right corner?

is the Larian Launcher version 4.44.97980? [look bottom left

If you do a scan on this forum you will see that it has been reported repeatedly pretty much since game launch. I (who don't care about multiplayer, achievements, or any sort of extra-pc saving/syncing methods) stopped using the Larian launcher to play at that time and I have never gone back. There are no more mismatches for me.

Unfortunately i got this mismatch error as well and i got no clue why, because most likely there are no integrity issues.

The launcher is a mess, i wish i could start it without the launcher, but unable to find out how i could avoid it. Any clue?

I had in mind the game is "fixed now"; so i got it very late... but it seems still buggy.

I have the very same mismatch data error. I tried following step by step the advices Larian are giving but I just dont get something : when they say to go and look up a certain data log in appdata (wich i did), they don't say what to do with it. I opened it and there is a bunch of lines pointing at files. What should I do with it ?

And for the record, i can launch the game without any issue. I didn't have the time to play since the update, just checked it if worked so I dont know if i will experience crashes in the future.

So my question is : does this mismatch data thing invove only launching issues ? Can I disregard this ?
Or is there a possibility I will experience bugs and crashes if I don't adress it now ?

Thank you for your time, i'm a bit lost since this is clearly not my domaine of expertise :)

/Edit : actually while typing this message I proceeded to verify the files via GOG.
It just ended and i don't have the mismatch dada warning anymore.

I'll leave my post for whoever needs it.

Best of luck with this issues guys

1 the files in appdata tend to be logs with the most import one called alteredFiles.txt
if the Larian launcher detects a mismatch it will make this log and you can open it to find the file that caused the flag i.e, what file Larian launcher thinks shouldn't be there will be listed in that alteredFiles.txt and if you don't have an issue then that alteredFiles.txt wont be there

2 yes verify is always worth a try

3 the mismatch data could be anything, an image, a stray txt file and mods are the most common cause but Gog sever also sends corrupt files when it goes out of sync... the larian launcher just has a list of what files should be there and flags anything else