answer 18 from this community created faq should solve ur issue
The problem is the application won't start up to show any error message. I have recovered from restarts before by the linked methods. But not even full uninstall and reinstall works this time. There is a work around to use another system and transfer the backup wallet file. I was thinking along the lines of a raspberry pi but the links on bit.diamond for that takes me to a slack channel or 404. I can install on another windows. Or could you suggest another system?
You can always use the method of transferring your coins through the export and import of the private key.
In addition, you can always run a virtual machine with Win7 or Win 10 with DMD wallet on a server or on any computer with 8 GB of operational memory and an SSD disk.