Thank-you for the help. I posted the same message on Brighthand and received similar advice. I was loath to edit the registry as I am not computer-savvy. However, I did the following:
Followed the instructions at
www.phm.lu/PocketPC/RegTweak...weak.asp?ref=49 to change the name of my SD card. Didn't see any change w/Resco Explorer on either CF or SD cards. Went back and deleted the tweak to change names.
Deleted the Inbox.mstxxxxx.xxxx folder from the CF card (after unchecking the 'store attachments' option).
Removed and reinstalled both storage cards, SD first, then CF.
Checked the 'store attachments' option.
Now have Inbox.mst.xxxxxxx.xxxxx on my SD card!! So I didn't seem to make any changes, but have the desired result.
Now I just have to hope that it remains this way!
K