Looks like the fix for this issue was posted on that same BlackBerry Forum page that you linked to your post abouve. Here is what worked for another user that was having the same issue:
From your desktop manager you must update/install your language and input support. Having done this allowed me to successfully download the email setup application again.
I will monitor this post to verify the resolution of this issue.
I was prompted to update the email setup assistant in order to activate my email accounts. After numerous prompts claiming the new update may not work properly when installed, I continued with the update. When asked to reboot, it stopped at 100% update bar and then froze!!
On the Blackberry site forums also mentioned the same problem even with other Blackberry phones. This is quite annoying since I would really like to access my emails. What to do. Can anyone help with this matter!!!!!
Tuesday - last edited Tuesday
I also have this problem, but with a Torch. It bricked my phone, so I had to reload the operating system. I updated to the most current version. I went back to the email setup program, so as to add a new email address, and the setup program checked for updates and asked me if I wanted to upgrade. I said no, so it stopped running the program. As it happens it will not allow you to use the program until you update, but it does not survive the update. There are a series of underlying modules that the program update gripes about -- that it requires newer versions of certain modules than the ones that exist on the Blackberry. But, as I said, I have upgraded to the RECOMMENDED current version of the OS.
Help please. Because of this, you have left me with a useless phone in the middle of a conference far, far away from my backup (I don't carry them on my laptop when travelling for security reasons!).