How do I recover colors on Outlook calendar after an update the color features are not available.

Hi @Michael Cohen, 

I hope you’re doing well today. 

Based on the information you shared that your calendar colors no longer appearing in the new Outlook for Windows after the recent update, and the color features not being available when you try to categorize events.  This behavior can occur because the new Outlook displays calendar colors through Color Categories, and those categories may not be available if the category list has not loaded correctly or has not been recreated after the update.  In addition, category support can vary by account type, so when the calendar is connected to an account that does not fully support categories, the categorize options may be limited in the app.  

To get your colors back, please follow the steps below in order, as each step builds on the previous one. 

1/ Create or refresh your category list in the new Outlook, then apply it to a calendar event. 

• First, open the new Outlook and go to Settings, then select Accounts, and then select Categories. 
• Next, create a new category or edit an existing one by choosing a name and a color, and then save your changes. 

• After that, return to Calendar, right click an event you can edit, select Categorize, and then select the category you just created so the color appears on the event.  

• References: 
  • Create and assign color categories in Outlook - Microsoft Support 
  • Assign a color category to a calendar event in Outlook - Microsoft Support 

2/ Update categories in Outlook on the web to trigger a clean sync, then restart the new Outlook app. 

• To begin with, sign in to Outlook on the web and create or edit a category under the Categories settings so the category list is saved to the mailbox. 
• Then, apply that category to a calendar event on the web and save the item. 
• Finally, fully close the new Outlook for Windows and reopen it, because restarting the app helps the refreshed categories appear in the desktop experience. 
• Reference: Use categories in Outlook - Microsoft Support 

3/ If your calendar is connected to a non-Microsoft account, add an Outlook.com mailbox and set it as the primary account for category controls. 

• First, go to Settings, then Accounts, and add an Outlook.com mailbox, or create one if needed. 
• Next, in Manage accounts, set the Outlook.com mailbox as the main account, because this can restore category options for calendars that otherwise show limited categorization in the new Outlook. 
• Afterward, close the new Outlook and reopen it, then try categorizing a calendar event again to confirm colors are available.  

I hope the information I shared earlier was somewhat helpful in addressing your issue. If you have any further questions or updates, please don’t hesitate to share. I’m always happy to assist further if needed.      

Thank you for your patience and your understanding. I look forward to continuing the conversation. 

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If calendar colors or category colors disappeared after an update, the available recovery options depend on which Outlook client is in use.

1. If using Outlook for Android or iOS
   • Category colors on mobile are read-only and must be configured on another Outlook endpoint (Outlook on the web, Outlook for Windows desktop, or Outlook for Mac).
   • Ensure categories and their colors are still set on the mailbox using Outlook on the web/desktop/Mac.
   • After confirming the categories there, restart the Outlook mobile app so it can refresh the category colors.
   • On mobile, category labels can be viewed by opening an event that has a category and expanding Show More.
   • It is not currently possible to create, edit, or change category colors directly in Outlook for Android or Outlook for iOS.
2. If using Outlook on the web / new Outlook and only calendar background colors changed
   • Calendar color (not per-item category) can be customized per calendar:
     • In new Outlook, go to Calendar view → select the calendar in the left sidebar.
     • Click the ellipses (…) next to the calendar name (or right‑click the calendar name) → Color.
     • Choose one of the standard colors, or select Color > Custom to pick a custom color or enter specific hex/RGB values.
   • Only one custom color per calendar is supported at a time.
3. If the Out of Office color changed after an update in classic Outlook for Windows
   • There is a known issue where items with Show As = Out of Office changed from the expected purple to a light blue or another light color after certain builds.
   • This issue is fixed in Outlook Version 2406 Build 17726.20000 and later. Updating Outlook to that or a newer build restores the expected behavior.
   • As a workaround on affected builds, a registry setting can be used:
     1. Open regedit.
     2. Go to HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Preferences.
     3. Create a new DWORD (32-bit) Value named DisableAestheticPatterns.
     4. Set its Value data to 1.
   • This workaround changes how Outlook renders calendar colors and can help distinguish Out of Office items again.

If the update removed or changed theme/dark mode rather than calendar colors, adjust theme and appearance under Outlook Settings → General → Appearance (in new Outlook) or the Office Theme settings in classic Outlook.

References:

• Calendar Category colors
• How do I enable Calendar Category Colors on Outlook for Android?
• Outlook Desktop calendar Out of Office color indicator unexpectedly changed
• Personalize your Calendar experience