Currently there is a known issue with the Unified Interface (UCI) in Dynamics 365. When accessing Dynamics 365 apps that are utilizing the UCI you may receive a generic "Access Denied" error message with a blank page. Things to note:
- This error only appears to be occurring in Internet Explorer version 11.316
- Only certain site map customizations are causing the error
- This error has also been seen in the UCI regarding PowerApps
- The error began with an Internet Explorer update that was released on February 12th, 2019 (i.e. KB4486563 for Windows 7)
The current resolution is to install the hotfix via the URL below. Make sure to select the correct build for your Windows version.
If you are unable to update your Internet Explorer version using the fix package manually (perhaps due to IT restrictions), a temporary workaround would be to use a different browser other than Internet Explorer to access your Dynamics 365 apps for the time being. The fix will be automatically deployed to windows updates in the next "patch Tuesday" update, which is currently slated for March 13th, 2019.