I can't attach documents in TEAMS for assignments.

Dear @Graham Smith, 

I hope you're having a nice day. Thank you for reaching out to the Microsoft Q&A forum and for sharing your concerns.  

The error message you're seeing “There was a problem attaching this file. Please remove and try again.” is typically points to a local sync or permissions issue. The good news is that there are several steps we can take to help resolve this. 

To better understand the situation and guide you toward a solution, could you share a few more details below such as: 

1. What type of file are you trying to attach (e.g., PDF, Word, image)? 
2. How large is the file?  
3. Are you uploading in a chat, channel, or assignment tab? 
4. Does the issue occur only in the desktop app, or also in the web or mobile version? 
5. Are you able to upload other files successfully? 
6. Have you tried uploading from a different device or network? 
7. What operating system are you using? Windows or macOS? 
8. Were you previously able to attach documents to assignments in Teams, or is this your first time attempting to do so and encountering the error?  
9. Could you please share the troubleshooting steps you’ve already tried so far? 

This will help us better understand the context and provide more targeted support. Any additional information will help us better understand and support you.   

To move toward a resolution, please consider the following actions: 

Make sure your device’s operating system and the Teams app are both up to date to avoid compatibility issues and ensure smooth performance. 

1/ Try Using Teams Web App: Visit https://teams.microsoft.com and attempt to attach the file there. This bypasses any desktop app-specific issues. 

2/ Check File Size and Format: Make sure the file you're trying to attach is under 500MB. Supported file types include Word, PDF, PowerPoint, Excel, and common image formats. 

3/ Compress the File: If the file is large or contains embedded content, try compressing it into a .zip file before uploading. 

4/ Test the File in Another Team or Chat: Try attaching the same file in a different team or private chat. This helps determine if the issue is specific to one channel or assignment. 

3/ Upload via OneDrive: You can upload the file to your OneDrive first, then attach it from there within the assignment submission window in Teams. 

4/ Check OneDrive Sync (if applicable): If the file is stored in OneDrive, make sure it’s fully synced and accessible from your device. 

Note: As community moderators, we kindly ask for your understanding that our access to internal development details is limited. Our primary role is to guide users toward the appropriate resources and support channels. While we may not have visibility into perform deeper backend analysis, we’ll continue doing our best to support you within the scope of our responsibilities.   I hope the information provided proves useful. Please proceed with the outlined steps and let me know whether they resolve the issue. If not, I’ll be glad to continue working with you to find a solution. 

Thank you for your patience and your understanding. Should you have any questions or need further assistance, feel free to reach out at any time. 

I look forward to hearing from you.  

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