in o365 calendar there is 1 entry listed but I cannot find it

Dear @Ian Edward Buchanan, 

Thank you for posting your question in the Microsoft Q&A forum.   

I understand how inconvenient it must be to see an entry showing in your Office 365 calendar but not be able to locate its details. 

Please see the following workarounds that will help you verify the issue: 

Option 1: Check your calendar using Outlook on the web 

Clear your browser cache to remove outdated or corrupted files:   

• For Google Chrome:        

Go to Settings > Privacy and security > Delete browsing data.        

Select All time, check both Cookies and other site data and Cached images and files, then click Delete from this device.          

• For Microsoft Edge:        

Go to Settings > Privacy, search, and services > Delete browsing data.        

Select All time, check both Cookies and other site data and Cached images and files, then click Clear now to proceed.           

Once you've completed these steps, please sign in to your account via office.com and navigate to the Apps section > Select Outlook and then check your Calendar. 

After clearing the cache, please open a private or incognito window in your browser to continue:   

• For Google Chrome:     

Click on the vertical three-dot menu and select New Incognito Window.       

• For Microsoft Edge:    

Click the horizontal three-dot menu and choose New InPrivate Window.      

After opening a private window, please return to the Outlook web page.  

If you’ve been using a different browser, such as Google Chrome, please try downloading Microsoft Edge and visit office.com to see if the issue persists. 

Option 2: Clear Outlook cache   

Close the Outlook app completely.  

Open the Run dialog by pressing Windows + R.  

Type or paste the following command and click OK:  

olk.exe --devtools  

The new Outlook will open (you may need to sign in), and the DevTools window will appear.  

In DevTools:   

Click Application on the toolbar.  

Clear local storage cache: Under Storage, find https://outlook.office.com., under Local Storage, right-click it, and select Clear.  

Clear cookies: Under Cookies, locate https://outlook.office.com., right-click it, and select Clear.  

Close the DevTools window.  

Once completed, the cache for the new Outlook will be cleared. Please note that this process removes temporary files, including saved login credentials, so you may need to sign in again. 

Option 3: Repair the Outlook desktop app    

Repair the Outlook app to fix any corrupted files or configuration issues that might be causing the problem.       

Note:       

If you proceed with this step, all app settings and saved login information will be reset. This means you may need to reconfigure your preferences and sign in again after the reset.        

We recommend backing up any important settings or data beforehand, if possible.       

This article provides further guidance on the topic: Repair an Office application - Microsoft Support 

Option 4: Reinstall the Outlook application 

Uninstall the Outlook app. 

Go to office.com > Apps > Install apps > Microsoft 365 apps > Apps & devices > Install Office.   

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I hope this information is helpful. Please follow these steps and let me know if it works for you. If not, we can work together to resolve this.    

Thank you for your patience and understanding. If you have any questions or need further assistance, please feel free to share them in the comments on this post so I can continue to support you. 

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