I uninstalled 8965 through Control Panel and installed 8923, but still get the "Too many login attempts" error.

Is there a way I can reset the accounts to login?  

Many things could cause this issue but I suspect its an issue specific to your server since we haven't had any reports of a similar issues, If you create a ticket with us we can help get this sorted out for you. But as a quick fix you can always login by RDP'ing into the server Smartermail is hosted on since IDS doesn't block the local host, from there you can remove the IDS blocks.

Thank you!!!  Really good to know that logging into the SM server always works.  The IP being used to login to the mailboxes was blocked.  Problem resolved, but really strange this happened after an upgrade, and the mailboxes could be accessed last night...  

Hey Tom, glad to hear that did the trick! I have seen this once before in my own testing (Intrusion Detection Block) but wasn't able to replicate in-house to get a task escalated. Can I have you submit a ticket on this so we can take a look with you? In the meantime, adding an entry for that IP to Settings>Security>Whitelist with the Bypass IDS Brute Force toggle enabled - that should help keep your users in good shape in the meantime.