You do not have adequate free disk space on the Host'sFilesystem to make changes to the Windows 7 virtual hard disk as it is a monolithicSparse type disk that is occupying 66,960,621,568 bytes and you only have 60,314,300,416 bytes free on the Host. You need to have no less then the existing size and additional extra free space for operational overhead to manipulate the monolithicSparse type disk either changing it to a twoGbMaxExtentSparse type of disk or just expanding its current size of 65 GB to something larger.
So you either need to free up an adequate amount of free disk space to perform whatever actions you want or copy it to and external drive that has adequate free disk space make your changes, make sure it is okay and the delete the original and copy it back.