SPSS 24 error "document is already in use"

I am having a problem in SPSS 24, when I try to open my datafile I get the following error

The document is already in use by another user or process. If you make
changes to the document they may overwrite changes made by others or your
changes may be overwritten by others

Can someone please help me, and explain step by step (in simple language)
how to fix this?

Maybe you are on a network (like a LAN =local area network) and maybe there is an other user that is using that file.

Maybe you can copy the file to your own computer and open it from there.
Thank you for the response.

I am not on a local network so no one else could use the file.

I already tried to reboot my computer and restart everything. When I open a copy of the file I get the same error.
If not in a network please verify you didn't open it twice .by mistake..
Please also change the title from "e" ...:)
Thank you for your response, I think the title was an accident

I did not open the file twice as I shut down the program and my laptop several times