Windows 7 and Vista, mapping networkdrive

First version: 04.09.2009, Andreas Kvapil
Update:        19.02.2010, Marc Petitmermet
                  - changed value to include NTLMv2
                  - added info for Home versions
               06.04.2010, Marc Petitmermet
                  - text formatting
               01.06.2010, Marc Petitmermet
                  - enhanced path to control panel

Windows Professional/Enterprise

After upgrading or even new installation of Windows Vista or Windows 7 there are problems with connecting network drives; the authentication level changed.

1. Start >> Control Panel >> System and Security >> Administrative Tools >> Local Security Policy >> Local Policies >> Security Options
2. find the Policy Key named Network Security: LAN Manager Authentication Level
   
3. set the value to Send LM and NTLM - use NTLMv2 session security if negotiated
4. reboot
   

Windows Home

The Home versions of Windows don't have a goup policy editor installed. Therefore, the registry must be manually changed with the registry editor.

1. start registry editor (search for "regedit")
   
2. open this key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. if it doesn't already exist, create a DWORD value named LmCompatibilityLevel
4. set the value to 1
5. reboot