Attachments wher not send sometimes


After upgrade to GW2014 R2 HF1 our press has sometime a curious problem.
The mail are composed in textview. When files are attached, they wasn't send sometimes.
The user often uses "resend" a message. Attachments and text are modified in this mail. Mails,who wrote before the upgrade was installed, don't work. New mails are working.
For the moment its the only user, who reported this issue.

A gwcheck on this mailbox don't show problems. I suppose, its a bug here.
I removed the gw client from the machine, clean the registry, restart the machine and install the gwclient again.

We running client 14.2.0 Build 123047 on Win7 SP1 Prof. 64bit
Is it a good idea to replace the installed client with a the GW 2014 SP2 client?

Any ideas?

Thanks in advance for your answers.


Dirk Emmermacher