"Set of Folders cannot be opened" error when trying to open shared calendar URL

Question

We are getting the "Set of folders" error when attempting to open a shared calendar via the URL in the email using Outlook 2016. 

Sharing works in Outlook 2013 and OWA, but all users on Outlook 2016 are seeing this error when receiving shared calendars. Owner right-clicks the calendar > share > chooses the user from GAL > sends the message. When the recipient gets the message, they click the URL to accept the shared calendar then get the Outlook pop-up "Set of folders could not be opened."

We have tried:

New profile

Safe mode

ResetNavPane

ScanPST

Deleted XML files in AppData

Repair

SARA tool

Uninstall/Re-install

Disassociated account from login.live

Regedit changes

To no avail. Has anyone come across this and have a fix? Can't find any suggestions outside of the above. Please help me figure this out. 

[Moved from: Outlook.com / Calendars and tasks  / Import, share, or open calendars]

Answer 1

Hi CSPilgrim,

Sorry for the delayed response. May I know which Outlook 2016 client version are users using? Please provide us with the detailed information, see What version of Outlook do I have?

Are you using Office 365 Exchange Online mailbox or On-premise Exchange Sever?

Make sure that Windows OS and Outlook client are latest update. If you are not using current latest build version of Outlook, please update the client. See check for Office updates

You may refer to the article to Share an Outlook calendar with other people.

Is it Download Shared Folders option disabled?

If so, please refer to the steps below to Download Shared Folders option enable to troubleshoot this issue.

• In Outlook, click File, click Account Settings, and then click Account Settings (again).

• Select the Microsoft Exchange account, and then click Change.

• Click More Settings.

• Click the Advanced tab.

• Select the Download Shared Folders option.

• Click OK, click Next, click Finish, and then click Close in the Account Settings window.

If still doesn’t work, try to turn off Cache Exchange Mode to check this issue.

Moreover, please provide us with a screenshot about the error message for further analysis.

To post screenshot, please refer to steps below：

• On the top ribbon, click on Insert Image, and then Choose File to browser the picture to upload.

• Click Upload.

Best regards,

Shyamal

Answer 2

Hi CSPilgrim,

I'm writing to follow up on this thread. If there are any updates on your side, please post back information above at your convenience.

Best regards,

Shyamal