onedrive sync issued, the system indicate the storage almost full but used 35%

Dear @siwakorn sukprasertchai

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

If OneDrive shows “storage almost full” but you’ve only used 35%, it usually points to a quota mismatch or sync cache corruption. Here are some suggestions may be helpful to you
Step-by-Step Troubleshooting

1.Check OneDrive Storage Details

First, let's make sure to verify the storage details to understand what might be consuming space.

1. Open OneDrive in your browser by going to OneDrive website.
2. Log in with your Microsoft account.
3. Click on the gear icon (Settings) in the top right corner.
4. Select Options.
5. Under Manage storage, you should see a breakdown of your storage usage.

2. Empty the OneDrive Recycle Bin

Files in the OneDrive Recycle Bin still count towards your storage limit.

1. On the OneDrive website, click on the Recycle bin in the left-hand navigation pane.
2. To delete all items, click on Empty recycle bin at the top of the page.
3. To delete individual items, select the files you want to delete and click Delete at the top of the page.

3. Check for "Shared with Me" Files

Files shared with you can also count towards your storage.

1. On the OneDrive website, click on Shared in the left-hand navigation pane.
2. Check if there are any large files or folders shared with you that you don’t need.
3. Remove any unnecessary shared files by selecting them and choosing Remove from my OneDrive.

4. Look for Hidden Files

Sometimes hidden or system files can take up space.

1. On the OneDrive website, ensure all folders are visible, including any hidden ones.
2. You might need to check each folder for any unexpected files.

Here is reference link My OneDrive says it's full
I hope it helps, if you have any other questions, please feel free to reach out

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