Hi, is it possible to donwgrade the OS, again, after we update to later version, and found out that some application won't work with the new version. If yes, how?

Also kindly advice how to do hard reset. Will all the email accounts and applications automatically "come back" after hard reset? Thanks.

Regards.

Here are some tips for downgrading your OS:

How do I downgrade the OS on my BlackBerry? - BlackBerryFAQ

A hard reset is s simple battery pull-remove the battery for approx. 30 sends, then re-install it. All of your e-mail and apps will restore.

Oh, so the "ALT" "shift" "del" is the same as pulling out battery hah? I thought it's soft reset. Well, is there a soft reset then for BB?

Thanks.