I first notice my notebook begins to have this issue when I tried to update my Windows. It returned me with error code "80070008", which says that my computer might have run out of memory, however, there are 200GB space available in my C: drive, and I am only using 27~30% of my RAM out of 8GB.

I tried to perform DISM 'ScanHealth' and it returned me "Error: 8 - Not enough storage is available to process this command".

At first, I tried to ignore this issue as I thought it did not cause me any major trouble. But I was wrong. Several USB devices become unresponsive (yellow exclamation icon at Device Manager). When I tried to manually install drivers, that's when I found out it was this STORAGE insufficiency again that cause me trouble:

"Windows found driver software for your device but encountered error while attempting to install it.  - Not enough storage is available to process this command".

Some of my programs also become incredibly laggy ever since this issue arises, yet I don't know where the problem lies. 

At Event Viewer... I noticed several error messages regarding "Windows was unable to load the registry. This problem is often caused by insufficient memory or insufficient security rights. - DETAIL: Not enough storage is available to process this command".

I also caught a glimpse of one error that I think stated more clearly: "Application popup: Windows - Low On Registry Space: The system has reached the maximum size allowed for the system part of the registry. Additional storage requests will be ignored".

Can someone help me address what issue I am actually having? How do I solve this problem? Please help. I have not done anything to this computer prior to this issue, especially something very sensitive like registry.

I have performed following troubleshoot attempts to no avail:

- Rebooted system.

- Disabled antivirus programs and firewall then tried Windows Update. Did not help.

- Ran Windows Diagnostic tools: Results addressed the issues and said they were "fixed", but problem is still there as if nothing is changed.

- Reset Windows Update components (both running fix tool and manually)

- Tried to run SFC /SCANNOW command, but it returned me "Windows Resource Protection could not perform the requested operation" message.

- Memory Diagnostic tool: No problems/errors detected

- Clean boot and Safe Mode. Problem is still the same.

- Ran CCleaner (only after this issue arises). Problem is still the same.

[Update 1]

-As suggested by Bruce Wooding-

Scanned my PC using Windows Defender Offline, Malwarebytes Anti-Rootkit, and Malwarebytes. Result showed no threats/malware/virus detected.

• Edited by Freya_L 13 hours 55 minutes ago

Thank you for your reply, Bruce.

After running Windows Defender Offline (if that is the rootkit revealer you mentioned), I also scanned my computer using Malwarebytes Anti-Rootkit and Malwarebytes. All them returned the same results, saying there was no malwares/viruses detected.

I think I may resort to re-installing my Windows. I wonder if that's a good idea..? To be honest, at this point, I don't mind backing up all my personal files and clean install my OS once and for all.