Encryption disabled network data

[BertTheBee]

While setting up my new phone (HTC One ST, a China-only dual SIM phone, running Android 4.0) to connect to my work's MS Exchange email, it walked me through some steps to encrypt the phone's storage card that it said my work server required. I followed the prompts on my phone, and afterwards I no longer have any data connection over the phone network. Data over wifi is fine, including connection to my work email, no problem. But no data traffic over the phone network when I'm not connected to wifi. The upload arrow flashes away, but the download arrow stays dark and no data moves.

Did a factory reset to unencrypt everything and back to square one. Tried the steps again with the same results -- after encryption network data traffic doesn't work. (It works fine before encryption.) HTC support over email could not help. Anyone know of a way to re-establish network data traffic after going through the encryption process, or something to do during the process to avoid the trouble after?

Colleagues using iPhones and Samsung phones had no problem like mine. Also Touchdown by Nitrodesk can connect on this phone to my work email, but I would much prefer to use the native email for better integration with the other apps.

Thanks for any help.