[Evolution] "Cannot get message", why?

[mario chiari <ml mariochiari net>]

Hi

I get the following error msg, and I am unable to open the mail:

> >
Unable to retrieve message.

Cannot get message 1561467844.28747_17255.fedora-pc from folder
/home/mario/.local/share/evolution/mail/local/.<my_folder>: No such
file or directory
<<

File 1561467844.28747_17255.fedora-pc:2,FS is within my 
/home/mario/.local/share/evolution/mail/local/.<my_folder>/cur .

Any hint?
thanks
mario