I face this issue when my VMWare could not open the virtual machine and was giving error: Failed to lock the file - Cannot open the disk *.vmdlk or one of the snapshot disks it depends on.
Cannot open the disk 'G:\VPC\WinXpPro\Windows XP Professional-000001.vmdk' or one of the snapshot disks it depends on.
Reason: Failed to lock the file.
Resolution: To solve this issue I opened the folder that has my virtual machine files ('G:\VPC\WinXpPro\). I found couple of folders that are named as ***.lck. I select them all and deleted them. You can also try to rename them if not comfortable with deleting them.
Windows XP Professional-000002.vmdk.lck
Windows XP Professional.vmdk.lck
Windows XP Professional-000001.vmdk.lck
Windows XP Professional.vmx.lck