A number of people are having the same problem as me, when you post as
a response to an ongoing thread, in place of your message, the
following message appears:
An embedded charset-unspecified text was scrubbed ...
and a link is given that leads to the desired message.
It's better than nothing
When you reply in gmail be sure you are using Plain Text
and not Rich Formatting. If you press Reply or Reply All and
you see immediately above the text entry area
B I U ... Plain Text
then you are in Rich Text mode. Click on Plain Text at the right
of the line just above the text entry area