Had problems accessing a network drive (Netgear ReadyNAS Duo) in Windows 8.1.
There was no way to access it and all I got were error messages. So, what can you do in this case?
I figured that I must have entered the wrong user/password combination and chose that Windows should remember what I've entered. OK, it's my bad but I need some files from this drive.
Press the Start button and type 'Credential Manager'.
When it opens up there's a list of all saved Windows credentials, certificate-based credentials and generic credentials.
So my NAS drive was listed among the other Windows credentials and all I had to do was to remove them by pressing the 'Remove' link.
Everything works fine again.