Updated Windows 10 and ever since when I try to open LR I get message saying it can't open because other application has it open
When Lightroom is running, there is a lock file present to prevent other users from accessing the catalog.
The lock file is normally deleted when you close the program, but if it doesn't close properly (crash or power failure), the lock file may not be deleted, and Lightroom will give you the error message that you mention.
The solution is to delete the lock file using the File Explorer.
Go to the folder that contains your LR catalog (usually inside the Pictures/My Pictures folder under your username.
Delete the file that ends with .lock - do not delete anything else.
Now try to launch Lightroom.
correct...but I can't figure out how to mark this response as correct in the thread. Worked like a charm. Thanks so much
Good to know that it worked for you.
Click the button with the green star and Correct Answer in my reply to mark as correct.