Windows always asking for more space although I've allocated 120GB!!

I use Parallels on a Mac and I run Windows with it. I only have MS Office installed and I use it for very few things. I do not store any files in the pvm, but rather on my Mac hdd. Even so, my pvm takes up 90GB. As recommended by Parallels support, I used "scanner.exe" to see what takes up my disk space. 80GB is in Windows and Windows installer (screenshot attached).
In the meantime, Windows has been asking for an extra 8GB more to install updates. So I changed my disk size (expanding) to 100GB and then to 120GB. Regardless, Windows keeps asking for those 8GB.

Something is definitely wrong with my Parallels installation. One odd thing I noticed, is that although I have Windows 10, inside the pvm there is a massive Windows 8.1-0.hdd (attached screenshot).

Any help will be deeply appreciated.
I'm already looking for alternatives to Parallels, so any guidance in that direction will also be of help.

 

Hi @CharalamposB , please make use of any file analyse application , analyse the C drive of your Windows virtual machine and check if can find any unwanted data.

 

Hi CharalamposB. Snapshots are included in the size of the '.pvm' file. You can refer this article to delete the snapshots (if any) which will reduce the size of the '.pvm' file. Regarding the virtual hard disk size, start the Windows virtual machine, open File Explorer and check the total size of 'Local Disk C'. If it still shows only 100GB in spite of 120GB, follow the steps from this article to increase the hard disk space. If you have upgraded your Windows virtual machine from Windows 8.1 to Windows 10, then you will find the '.hdd' file name as 'Windows 8.1-0.hdd' only.

 

I solved it.
Turned out that my Mac was keeping invisible local backups which were taking up space. The occupied space showed up as "Purgeable" on the HDD info popup, hence "Available". Parallels did not check how much disk space it could actually claim and was allowing me to increase the VM size, with the "expanding" option ticked, to 120GB. But when it came to the VM actually using the allocated GB, it could not expand to "Purgeable" space - although I believe the iOS is supposed to avail such space on application request. So neither my Mac iOS freed the space for the VM, nor did Parallels know that purgeable space would not become available when it allowed me to increase the VM size...

 

I forgot to say, that once I discovered the problem and deleted the backups, Parallels would still fail to see the free space.
This was because in order for the VM to expand to the available space it needed the free space to be in an adjacent partition. I downloaded MiniTool Partition Wizard (free tool) and did what was necessary.

 

Good to know that it's sorted out. Please post again for any additional queries.