Its is installed in my Steam folder which is on my spare hard disk, which is not inside a Program Files folder, nor do I see how that could cause a problem.

Are you sure the folder it is installed in is not marked Read Only, or have you tried running Toribash as an administrator (not that you should do so, but if it helps that gives us a few clues).

If it's not in Program Files though, most of the potential issues are avoided. Program Files has some UAC-related permissions things that Toribash generally won't handle gracefully.

Nothing is marked Read-Only (apart from my broken USB xD). And as I said, I installed different versions of Toribash, meaning that Read-Only cant be the problem. I tried administrator, it didnt work, its the first thing you should try in these kinds of situations.
-----
The only way that Read-Only can be a problem is if Toribash has some side folder that it needs to run (for example, something in the AppData\Roaming folder is installed as a side folder that needs to be there to run programs). But I cant find any folder like that. I also deleted and reinstalled the registry files.

The problem fixed itself?

I dont know what happened, all I know is that my router is working again and that I can login with other accounts.

As far as I know, i havent done anything to my PC. No installing, uninstalling, messing with system files, anything.

That leaves me with one conclusion, it must be the routers fault...

If this problem is to happen again I'd right click the toribash Icon, then go down to properties, and above are 5 tabs, click local files and go all the way down to Verify Integrity of Game Cache. Once it has all downloaded it may work, I believe it would solve it if this problem persists, hopefully it does not

Ofc I tried that, thats one of the first things you should try, apart form running as administrator. And as I said, I tried many versions: standalone, outdated standalone, Steam, reinstalling, reinstalling registry files....