Unable to shrink a partition

[JackST]

I cannot get my main partition to shrink.

The capacity of the only drive on my laptop is 240GB, of which 116GB is free space.
When I open disk management and try to shrink my C drive it says, "size of available shrink space in MB 42882". Attempting to shrink the drive by this (or any amount less than this) gives the error "There is not enough space available on the disk(s) to complete this operation."

I have disabled hibernation mode, the page file, deleted pagefile.sys. There is no hibernation file that I can find.
I have tried several different 3rd party partitioning software's and none seem to work.

Any help would be great. My end goal is to dual boot ubuntu with windows 10.

Cheers

 

[asoroka]

42GB would be enough for ubuntu anyway.

Have you tried running Disk Cleanup yet.

Have you emptied the trash?

 

[JackST]

It would be enough yes, but as I said in the original post, disk management does not let me shrink the partition.
Yes, I have tried disk clean up and disk optimisation.
Yes, I have emptied the trash.