Archive for November, 2013

RDP “Logon attempt failed” Errors on Windows 7 and Windows 8

Tuesday, November 5th, 2013

Quite suddenly I found that I could no longer log in to various servers on my local network with RDP using a domain password. Local passwords worked fine.

The problem turned out to be related to running RDP 8.0 on my client machines. After much cursing and swearing I found out that all I had to do to fix the problem was modify one group policy on each of the affected workstations. The policy in question was:

\Local Computer Policy\Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\Network Security: LAN Manager authentication level

and it needed to be changed to

Send LM & NTLM - use NTLMv2 session security if negotiated

Wasted an entire morning on this. What a PITA!