Public Folder Messages are Blank — Message bodies appearing blank in messages within public folders?

We have a large number of public folders used to hold e-mail messages.  I
have found recently that some, but not all, folders have messages that do not
have any content.  These messages did have content when they were
moved/copied to the folders.

SOLUTION:

In my case problem is solved  by switching off integration of Eset NOD32 antivirus with email clients. Desabel mail filter in NOD32.