Work with a Virtual Machine Without Saving Changes

If you don't want your virtual machine to store the changes you make to it during the working session (for example, when testing some guest OS programs that may damage the guest OS), you can start the virtual machine in Safe Mode:

1. Start Parallels Workstation.
2. In the sidebar , select the virtual machine that you want to start in Safe Mode and click Virtual Machine > Safe Mode .

Set a Virtual Machine to Always Start in Safe Mode

If you want your virtual machine to always start in Safe Mode:

1. Start Parallels Workstation.
2. In the sidebar , select the virtual machine and click Virtual Machine > Configure > Options > Security .
3. In the Security pane, choose Ask me what to do from the Undo Disks menu and click OK .

Note: If you have the automatic compression of virtual disks enabled in the Optimization pane , it will become disabled after you enable Undo Disks .