how to allocate unallocated space to c drive?

I think that the D drive should be moved to right side (in your picture) by some amount, so that the free space will appear between C and D. Then the C drive can be extended.

Unfortunately, the Disk Management tool cannot perform such movement. There are several “Partition Management” tools that can be used:

• https://www.bing.com/search?q=Partition+Manager+Windows+11

The free versions should work.

Make sure to back up your important files.

Hello,

Thank you for posting in Microsoft Q&A.

Based on the description, I understand your question is related to allocate unallocated space to c drive.

Before making any changes, ensure you back up important data to avoid any potential loss.

Press Windows + X and select Disk Management.

Right-click on the D drive and select Delete Volume. This will convert the D drive into unallocated space.

Right-click on the C drive and select Extend Volume.

Follow the prompts in the Extend Volume Wizard to add the unallocated space to the C drive.

Have a nice day.

Best Regards,

Molly

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