sorry for my bad english ;)
i have got a strange problem with tiki 6.x, windows server 2008 r2 64...
I tried today to set log in (ldap) to an active directory on Windows 2008 r2 server.
I don't know a lot about Ad (or windows ) so i cound't understand a lot. I was with 2 guys that couldn't figure what TW is expecting (fields variables or format).
When i tried to login i got usually a "Fatal error: Call to undefined method Net_LDAP2_Error" or invalid password (i tried also the "forgot password" thing and then the user wasn't found).
Can you post here a screenshot of your configuration maybe it will help. Thank