strange problem when closing WL folder

Hi all,

Have noticed a problem when closing a folder, which seems to occur
under these conditions:

1. The folder contains refiling marks.
2. I have earlier had, in the same Emacs session, open files from
removable media, which is no longer mounted.

What happens is that Emacs says it cannot open some file on the disk
that is no longer there, and it refuses to proceed with the WL
refiling.

The only solution I have found is to close and re-start Emacs.

(I have not noticed this, or any similar, problem except when using
WL.)

Any ideas how to fix this?

/Tomas