Is it possible to reset password history in active directory to a specfic point in time?
For example I want to keep history of passwords changed after 01.03.2009 but not before 01.03.2009?
Thanks for help.
I don't know any way to reset the password history to a set point in time. I think (but am not sure) that if you change your policy to store the last three passwords then it keeps the last three paswords but discards earlier ones. If you know roughly how often your passwords need changing, e.g. if a policy requires a change every 30 days, you could use this to reset the password history to an approximate point in time.
There's no built-in functionality in the product to do what you're asking for. I'm assuming that you're referring to the "Enforce password history" functionality, and you're suggesting that you'd like to "retroactively" begin an "Enforce password history" policy starting with passwords that were set on the date you mention.
If that day was in the last 60 days (by default, unless you've changed the tombstone lifetime in your AD), it would be possible to perform an authoritative restore of a subtree of (or the entire) Directory from a backup taken on the date in question, and then turn on the "Enforce password history" feature at that time. Because the date you're mentioning is beyond 60 days old you cannot restore a backup, by default, of that age.
Even if you did have a date within the allowed restore window I wouldn't recommend doing that. You'd lose all the changes you made to the restored objects between the date of the restore and the present date, for starts. Secondly, restoring the AD isn't a process that I'd get into lightly. I've done it before, many times in labs and, thankfully, only a few times in production. Every time, in a production scenario, it's a bit of a "white knuckle" affair to make sure that you're doing exactly what you want (because any changes you make, when market authoritative, will replicate to all the DC's in the domain and global catalog replication sets). I only advise Customers to perform restores of AD when it's the last possible option.