The partition size of the C drive is too small and needs to be increased.

[simonmul]

The C: drive partition is just too small that's been setup from HP, the D drive partition is no issues and very large. The issue we have is that the system files and windows is completely filling C: and we cannot even do updates. Is there any way to increase C:

[erico]

Sure.

You do have options.

You can safely delete everything in  the Windows.old folder.

or

Install a higher capacity M.2  or 2.5" SATA3 SSD or  a legacy HDD  and clone the original disk to it. 

Since you have a desktop PC, that is quite a straightforward process.

[simonmul]

Thank you, appreciate the support and will give that a go. The HDD I have is a good size drive, it seems that it is partitioned to C and D. The C however is just too small and is struggling / full while I have LOTS of space available on the D partition. Is there any way of making the C partition bigger?

[erico]

What is the storage capacity of your disk?

What is the capacity of the C partition and the D partition of your disk?

Isn't the D partition your recovery partition?

Can you provide an image of the Disk Management dialogue Window for your PC?