You may run into the following error when attempting to edit the “Standard” enterprise calendar or creating a new one. It’s a bit puzzling because you can open projects through Project Center (Select a project > Open > In Microsoft Project for Editing. If you can do that, you know that your browser can communicate with Microsoft Project 2013 or 2016. Also – you may be able to create a new calendar without issue, but editing produces this error message:

There are several things to try:

Use a Different Browser

I’ve seen this issue happen in Chrome but if I tried it in Edge, Firefox or even Internet Explorer I would then be able to edit the calendar. Nice and simple!

Clean Up Your Account Profiles in Microsoft Project

Occasionally the account profiles in Microsoft Project will get corrupted (not often but it does happen). To clean them up, perform the following:

  1. Open Microsoft Project
  2. Click on File > Info > Manage Accounts > Configure Accounts
  3. Change “When starting” to Choose an account
  4. Select each profile except Computer and click on Remove and then OK
  5. Note: if you are currently connected to PWA, you will not be able to delete that profile. Perform the following in this case:
    1. Close and re-open Microsoft Project
    2. Choose the Computer profile
    3. Delete the remaining profiles except Computer
  6. Close Microsoft Project
  7. In PWA, open the Project Center
  8. On the Projects Ribbon, click on New > In Project Professional
  9. If prompted, click on Yes
  10. Microsoft Project should open successfully
  11. Switch back to PWA and try to edit the calendar

If Using Internet Explorer, Add PWA to Trusted Sites

This only applies to people still using Internet Explorer and not Edge, Firefox or Chrome:

  1. Open PWA in Internet Explorer
  2. Click on the Gear Symbol > Internet Options > Security > Trusted Sites
  3. Click on Sites and add the PWA URL
  4. Click on Close
  5. Click on OK

Click To Run (CTR) / MSI Mismatches

There have been some known issues if you have mismatched installs of Office 2013/2016 applications. What this simply means is that you have installed some apps from the Office 365 portal (aka Click to Run or CTR) while other apps were installed from traditional media (MSI). In order to fix this, uninstall the MSI version of the application and then log into the Office 365 portal and install the application from there.