I had the curious case that on my domain-joined laptop from work, two applications kept asking for usernames and credentials after a recent change of my Windows password.

Logging on to the laptop was no problem after the change, and most applications also accepted the new password (via passthru), or at least asked only once for the new one.

Problem

But there were two outliers:

1. Outlook first started normal, but after a few minutes, a logon mask would pop up and ask for an username/password combo for a server I couldn’t map (I was on a VPN connection, and it was a machine from our domain, so it looked legit, but we have cryptic server names).

   Anyways, I entered my new password and hit OK – a few seconds later, the masked showed up again… and again… and again…, preventing me to use Outlook.

   Of course I double and triple checked if I maybe had mistyped the password (no, I didn’t) and I also set the checkbox (“always use this”), but to no avail: Even after reboots, this issue persisted.

   After a while, I associated it to have something to do with synchronising and accessing external mailboxes, but that insight alone didn’t help me in solving it.

2. Microsoft Teams then later also had authentication problems and couldn’t connect – and that was a week or so after I changed my Windows/AD password!

Solution

Interestingly, both programs also worked fine on other machines (e.g. in my Citrix desktop session), so I assumed it had something to do with my local user profile on the laptop, instead of the roaming settings. And since caching ist often a culprit (and one of the hardest problems in computer science 😉 ), I searched the internet for that.

I found hints on a page (can’t remember which one exactly, but it was similar to this), which explained how to clear the cached credentials (stored user names and passwords) from a Windows system:

• Call rundll32.exe keymgr.dll,KRShowKeyMgr and in the GUI window that shows up (titled “Stored User Names and Passwords”), select and delete the entry which you think is the troublemaker.

I only had two entries in the list anyways, one with the server name from the Outlook logon window, and one named “WindowsLive”, which turned out to be the one responsible for the Teams problem. After deleting these two entries, both Outlook and Teams asked me one more time for the credentials at their next start, but were silent from then on.

PS: There is also a command-line utility named cmdkey for this task, it seems. I believe it does the same as the GUI tool, but I haven’t used that one yet (on further reading: It applies only to server edition, according to the help page, so maybe not so helpful on a client computer after all…).