If you have ever encountered this error message anytime and it didn't worked out for you then remember there is a simple solution to it as easy as deleting a file/folder. I had this error earlier while either you reinstall a VMWare or you setup a new operating system. When I got this error again just recently I wanted it to plug it on as a post to my WordPress blog so that it can help someone or myself in future..!
What we need to do is simply go to the folder where we have placed the physical files for the specific virtual machine and just delete the folders which are ending with "*.vmx.lck" and you are done.
For example in respect to current situation which we see in dialog box I needed to delete 2 folders SUSE Linux.vmx.lck and SUSE Linux.vmdk.lck. That's it and VMWare Workstation will be happy to play the Virtual Machine again without any problem.