I started getting this error yesterday, Thursday May 7th, on boot (windows 7).
Turned out to be 2 startup entries for GOG, just disabled one of them today (msconfig).
Dunno how it happened though. Been forced to GoG 2.0 alot longer than 2 days, don't
think there was a GOG 2.0 update on May 7th, not updating windows (7 being dead and all).
Big mystery that.

Its been a while since last time i used the launcher, today when i tried to run Galaxy 2.0 the thing is showing the same message. No way around here for me yet.
Nevermind, the lock-files fix worked for now.

I have the same problem. I tried the lock-file deletion fix. It held 2 weeks. Now I have the problem again. I tried the lock-file fix, didn't work. I tried the regedit fix, didn't work. It's extremely annoying.

I too have this problem,
I've tried the lock-file deletion and that didn't work.

What's the registry fix? I'm looking everywhere and nothing works. I've never heard of the registry fix but I hope it will fix it for me..

I'm in this exact situation as well, including having the fix work the first time but not anymore. I don't remember how it started on the first time it happened (which was fixed by deleting file), but this second one was just after a crash/hard reset on my pc.

same it held for a couple of weeks the main issue is, you cant disable gog from launching on the 2nd account on the same pc -_-
so now i have to do as before; log in the other account and shut down the pop up there.
going to try and log the app in and rummage with the settings then, might find a work around hopefully since it keeps auto booting and ask for a log in... on the 2nd account

in the short duration i tested my work around.

it seems to be working, i am not claiming it is.

i have 2 accounts on my main pc one for myself and other half.

but you want to log in to the 2nd account and log in your gog launcher.
go to settings and disable launch on bootup / start up.

so far it is working for me letting me have the gog launcher auto boot up for my main account.
if need be you disable it in both accounts so that when either of the accounts log off with launcher exited, the other account can have full acces.

so far i rebooted a couple of times simulating my other halfs pc usage, usually be4 me.
managed to boot up gog no problem

Continues to happen. Fresh install. There is nothing in the lock-files. There are no other accounts on this computer.

Guess I'm not using GOG anymore

I've just started encountering this problem today. It was working fine last night, now after a reboot it comes up with this error.

Yes. I got the same error today. What's going on? GOG Galaxy used to work fine until now.

I experience the same problem. I believe it might be related to the newest update. The timing match in my case.

And I have only used this one GOG account on my pc.

Got the same problem today, restarted the computer and now it works.

Same problem here, GOG Galaxy won't launch ever since a reboot yesterday.
Restarting my computer did not solve it.
I do not have other accounts on my PC...

Same here, occurred first time today. Using only one account.