Yes - via Jim Woodhead's note in Evernote
Create a read only text file named INSTLOCK.TXT and copy to the ..\MAS90\HOME\ folder
to make read only ...click on properties and check read only box.
When done rename or delete file.
https://www.evernote.com/shard/s1/sh/14cb6fe5-d5d9-4399-9e53-5b348a6f204a/ee08448a057ba5e35aac5f1ad2913e27