I have a domain joined Windows 10 Enterprise (upgraded from Win 8.1) with a local user "x". I create a share and give "x" some rights on the share, Read or whatever. Folder rights are covered by "Everyone" but I can also give "x" explicit access, doesn't matter.

Now I do

net use \\mycomputer\share password /user:mycomputer\x

This works fine on my local machine and on two other Windows 10 computers, but not from a variety of Windows 8.1 machines (including freshly installed ones). The error shown is "Access denied".

When I look at the Windows security event log on the share machine I see a successful authentication for user "x", followed by a logon for that user and (only in case of "access denied") an immediate logoff.

Any ideas?


Found it with Wireshark by comparing a successful auth request with an unsuccessful one. The unsuccessful was suspiciously 9 bytes longer...

After digging into the deepest recesses of the NTLMv2 response I found the difference. I didn't use a FQDN on the computer name and while the (working) Win10 request set the Target Name attribute to plain cifs/mycomputername, the Win8.1 request set it to cifs/mycomputername.x.y.com where x.y.com was the primary DNS suffix.

So the solution was to use the FQDN on the username like

net use \\mycomputer\share password /user:mycomputer.mydomain.com\x

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.