Try this:
Look at your registry and see if it reads as follows.
[HKEY_LOCAL_MACHINE\System\Inbox\Templates\IPM\Note]
"Read"="
\\Windows\\HTC_read_note.htm"
If this true you need to change it to the following and reset your phone and all should be good.
[HKEY_LOCAL_MACHINE\System\Inbox\Templates\IPM\Note]
"Read"="
\\Windows\\read_note.htm"
This fixed it for me.
~John