There was also a problem on older releases where the windows password had to be all upper or all lower case to work. Mixed case passwords failed. It has been fixed, but I can’t remember how far back that was.
Also make sure your Windows Profile and AS/400 Profile Match, Profile and password.
Akso using WRKLNK or OPS Nav make sure Permissions on the AS/400 share is correct……Rick
You don’t tell us your OS version/release, so it’s difficult to be certain. For recent releases of OS/400 and i5/OS, there are PTFs that address the changes that Microsoft made. Contact your service provider for the PTFs that are appropriate for your site.