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Volume 30 Issue 37

Slipstick Systems

Issue Date: December 4, 2025 « Previous Issue | Next Issue »

The following articles were included in our Exchange Messaging Outlook (EMO) newsletter published on December 4, 2025.

EMO is a weekly publication. To receive your own copy of EMO by email, subscribe here.

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Today's Highlights »

  • Too Many Calendars?
  • Keep both Outlook apps?
  • Bug: Double Spaced Signatures

Too Many Calendars?

I’m often asked how to get rid of the extra calendars that show up in Outlook when you add an account.

If you are using new Outlook, you cannot remove the calendars. You can uncheck them in the Calendar list so events on that calendar don’t display but they cannot be removed from new Outlook.

If you are using classic Outlook, you can remove “Calendar (This computer only)" in IMAP mailboxes or calendars in PST files but not calendars in Microsoft Exchange accounts (including outlook.com). You can create a new calendar group and move the extra calendars to the new group, then collapse it.

To create a new calendar group, right click “My Calendars” group and choose “New Calendar Group” from the menu. Enter a name for the group (I name it ‘Don’t Use’) then drag the extra calendar folders to it. If one of the calendars you don't use is the default calendar in your default data file, don’t move it to the new group as it’s likely to get moved back to My Calendar and selected.

If you need to remove a “(This computer only)" calendar and it is not in your default data file, you can either delete (or rename) the data file and let Outlook resync the mailbox, or delete the folder using MFCMAPI, PowerShell, or VBA, but it may come back if you receive a meeting invitation sent to that email address. If you remove the account from Outlook and add it back, the “Calendar (This computer only)" folders won't be created (as long as a different data file is set as default data file) and rarely come back when you receive a meeting request. If you have events in the calendar, or contacts in the “Contacts (This computer only)" folder, move or export them before you delete the OST file or remove the account from Outlook!

To rename an IMAP data file, right click on the account name in the folder list and choose "Open File Location". This opens File Explorer with the IMAP data file selected. Close Outlook and add old to the file name or delete it.

See How to Hide or Delete Outlook's Default Folders for steps to delete a calendar using MFCMAPI, PowerShell, VBA for either IMAP accounts or PST files.

Keep both Outlook apps?

A user wanted to know if he should keep both classic and new Outlook installed: “I got a new laptop with Microsoft 365. I now have Classic and the new Outlook. Can I delete one of these?”

If you are not using new Outlook, you could uninstall it, but I usually tell clients to unpin it from the Windows task bar and leave it installed. It doesn't take up a lot of space and future updates may reinstall it. Unpinning it gets it out of sight, so you don't accidentally open it. If you really want to remove it, open Windows Settings > Apps > Installed apps. Find Outlook, click on it then choose Uninstall.

Classic Outlook is part of the Microsoft 365 suite, and you’d need to uninstall Microsoft 365 then use ODT (Office Deployment tool) to install Office without Outlook. However, currently, Word and Excel’s Send by email function uses classic Outlook as does Word’s Mail Merge. If you use those features, you need classic Outlook installed.

Bug: Double Spaced Signatures

There is a bug in new Outlook and Outlook on the web where the signatures are double spaced. Microsoft is aware of the issue and it should be fixed soon.

New & Updated Outlook Support Articles

Error “The text formatting command is not available” when opening emails in classic Outlook or documents in Word for Windows - Microsoft Support

My Templates are missing from Outlook - Microsoft Support

Other Resources

Auto-Archiving for Exchange Online

Update to EWS Access for Kiosk / Frontline Worker Licensed Users | Microsoft Community Hub

Volume 30 Issue 37 was last modified: January 15th, 2026 by Slipstick

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Latest EMO: Vol. 30 Issue 38

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  • Popular
  • Latest
  • Week Month All
  • Use Classic Outlook, not New Outlook
  • How to Remove the Primary Account from Outlook
  • Reset the New Outlook Profile
  • Adjusting Outlook's Zoom Setting in Email
  • How to Hide or Delete Outlook's Default Folders
  • Removing Suggested Accounts in New Outlook
  • OUTLOOK.EXE continues running after you exit Outlook
  • This operation has been cancelled due to restrictions
  • Shared Mailboxes and the Default 'Send From' Account
  • Add Holidays to Outlook's Calendar
  • Opt out of Microsoft 365 Companion Apps
  • Mail Templates in Outlook for Windows (and Web)
  • Urban legend: Microsoft Deletes Old Outlook.com Messages
  • Buttons in the New Message Notifications
  • Move Deleted Items to Another Folder Automatically
  • Open Outlook Templates using PowerShell
  • Count and List Folders in Classic Outlook
  • Google Workspace and Outlook with POP Mail
  • Import EML Files into New Outlook
  • Opening PST files in New Outlook
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Recent Bugs List

Microsoft keeps a running list of issues affecting recently released updates at Fixes or workarounds for recent issues in classic Outlook (Windows).

For new Outlook for Windows: Fixes or workarounds for recent issues in new Outlook for Windows .

Outlook for Mac Recent issues: Fixes or workarounds for recent issues in Outlook for Mac

Outlook.com Recent issues: Fixes or workarounds for recent issues on Outlook.com

Office Update History

Update history for supported Office versions is at Update history for Office

Outlook Suggestions and Feedback

Outlook Feedback covers Outlook as an email client, including Outlook Android, iOS, Mac, and Windows clients, as well as the browser extension (PWA) and Outlook on the web.

Outlook (new) Feedback. Use this for feedback and suggestions for Outlook (new).

Use Outlook.com Feedback for suggestions or feedback about Outlook.com accounts.

Other Microsoft 365 applications and services




New Outlook Articles

Opt out of Microsoft 365 Companion Apps

Mail Templates in Outlook for Windows (and Web)

Urban legend: Microsoft Deletes Old Outlook.com Messages

Buttons in the New Message Notifications

Move Deleted Items to Another Folder Automatically

Open Outlook Templates using PowerShell

Count and List Folders in Classic Outlook

Google Workspace and Outlook with POP Mail

Import EML Files into New Outlook

Opening PST files in New Outlook

Newest Code Samples

Open Outlook Templates using PowerShell

Count and List Folders in Classic Outlook

Insert Word Document into Email using VBA

Warn Before Deleting a Contact

Use PowerShell to Delete Attachments

Remove RE:, FWD:, and Other Prefixes from Subject Line

Change the Mailing Address Using PowerShell

Categorize @Mentioned Messages

Send an Email When You Open Outlook

Delete Old Calendar Events using VBA

Repair PST

Convert an OST to PST

Repair damaged PST file

Repair large PST File

Remove password from PST

Merge Two Data Files

Sync & Share Outlook Data

  • Share Calendar & Contacts
  • Synchronize two computers
  • Sync Calendar and Contacts Using Outlook.com
  • Sync Outlook & Android Devices
  • Sync Google Calendar with Outlook
  • Access Folders in Other Users Mailboxes

Diane Poremsky [Outlook MVP]

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