Windows 10: System data caused full C disk

2 weeks ago my C disk is still 80GB left , today its full but i dont download anything . i check and found out my system data is 120Gb unlike my other computer with only 40GB of system data . How do i delete the system data to clear my disk

:)

 

Change Boot disk assignment to system C: drivefrom data disk

After updating to Windows 10 I saw that my previous Windows 7 had assigned separate disk (G as a system drive with only two files not located on my system drive C: This was not related to the Windows 10 install,

I has used G: as a data drive but after WIndows 10 update and after relocating this data to another drive those two system files still remained. I could not delete or move these two files as they were System files. My WIndows 10 repair disk and startup
utilities were no help.

Any system backup and restore always included both the C: drive and G: drive.

I was able to create a G: drive partition on another drive but in restoring my C: drive system image the two boot files were still recovered to the drive separate from the system C: drive.

How can I get those system files back onto the C: drive?

The 2 system files contain language preference files and system setup graphic files.

Thanks for any suggestions on this.

 

GPT disk conversion for both data drives and C drive


Macrium Rescue disk can be used to convert from MBR to GPT and vice versa without doing a fresh install of Windows.

1. Download Rescue6.1.1081X64.iso - Google Drive and use Rufus to create a bootable USB disk. Skip this step if you've already created the Macrium Rescue disk.
2. Download: BootEFI_Only-00-00.zip - Google Drive . Unzip to an external or an internal HD
   NOTE: This is a copy of the first 3 partitions of my current Windows 10 x64 (450MB Recovery, 100MB EFI and 16MB MSR)
3. Boot up Macrium Rescue disk and create a backup of your current Windows to another internal/external HD. It serves 2 purposes: you'd have a backup of your current Windows in case things go wrong and then use it to restore the C drive on the next steps.
4. Next, switch the BIOS to UEFI and use Macrium to restore the first 3 partitions downloaded in step 2 to your current MBR Windows. No need to convert or Format, Macrium will do it.
5. Again with Macrium, select the backup image from step 3, and copy back the C drive after the 3 partitions.
   After this step, you should have: 450MB, 100MB, 16MB and C drive (GPT partition scheme)
6. From Macrium, click on Fix the Windows Boot Problems
7. Reboot. Your Windows should be in UEFI mode.

 

Lost data from hard drive, what to do now?

Well, I'm sorry to hear that it's a WD My Passport that failed on you, @tomhenry ! *Frown
I'd recommend you to try using a different USB cable with it and see if that will help your system to detect it without it disconnecting.
I'd also suggest you to go to Disk Management and see how the drive is listed there. It won't hurt to check up on the health and SMART status of the HDD by running the QUICK and EXTENDED tests from the WD's Data LifeGuard Diagnostics. Here's a link to the available software: http://products.wdc.com/support/kb.ashx?id=11ZOpD

Give these troubleshooting steps a try and keep us posted with the results!
SuperSoph_WD