Outlook developed a bothersome behavior. Seemingly on random days, it would change my work hours to be later than I set them. I’d shrug my shoulders, set them back where I wanted them, and then a few days later, they’d change again.

At first, I thought the domain admins were applying a group policy. I found that it gets saved in \HKCU\Software\Microsoft\Office\version-number-here\Outlook\Options\Calendar in the CalDefStart and CalDefEnd entries. I was thinking I’d set it where I wanted it, export the registry key, and load in in my StartUp folder.

Then I realized that it might be happening on the day after I used an HVD (Hosted Virtual Desktop). I suspect that what is happening is that when I use the Outlook in my HVD, that sets the working hours. It could be something borked in Outlook, or it could be that there is a policy applied to the HVD which is changing it, and then Exchange syncs it to my main Outlook. Since our HVD uses ProfileUnity to copy the user profile, I suspect that PU is doing it.