Hi kazi Muhtadi,
Thank you for reaching out to Microsoft Q&A forum. I understand how stressful it is when file uploads suddenly stop working, even though everything else seems fine.
Based on what you’re seeing, this issue may be tied to how the system file picker interacts with the Downloads folder. I can see that the Q&A assistant has already provided several suggestions. If the problem is still persisting, here are a few additional steps we can try next:
Step 1: Reset how Windows treats the Downloads folder
Sometimes Windows handles Downloads like a media folder, which can cause the file picker to hang during uploads.
- Open File Explorer then right‑click on Downloads and select Properties
- Go to the Customize tab and under Optimize this folder for, select General items
- Check Also apply this template to all subfolders
- Click Apply and OK
- Press Ctrl + Shift + Esc, find Windows Explorer and click Restart
After that, try attaching the file again.
Step 2: Turn off file previews (thumbnails)
File previews, especially for PDFs or ZIP files, can cause the upload window to freeze.
- Open File Explorer
- Click the three‑dot menu (…) and choose Options
- Open the View tab and select Always show icons, never thumbnails
- Click Apply and OK
- Restart Windows Explorer again
Step 3: Check for a corrupted file in Downloads
In some cases, a single incomplete or corrupted file can affect the whole Downloads folder.
- Open Downloads and change the view to List or Details
- Sort by Date modified
- Create a new folder (for example, TempDownloads) on your Desktop
- Move files out of Downloads in small batches
- After each batch, test attaching a file to see if the issue is gone
This helps narrow down if one specific file is causing the problem.
Since you’re up against a deadline right now, a quick workaround is to copy the file from Downloads into Documents or Desktop or a new folder (for example, C:\Uploads) and upload it from there.
If you try these steps and the issue still comes back, please let me know and we’ll keep working through it together.
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