"Create Task" in Version 5.0.0b results in "Error on Page"

[esher]

I'm running Version 5.0.0b (Build 3150), which is an upgrade installation from 4.5.1. In 4.5.1 I was able to use the "Create Task" functionality, but now when I click it I get an empty page under Tasks although my shortcuts and menu bar are still there. In the bottom left in IE I see "Error on Page"; if I click on that and view details it reports

Line: 51
Char: 1
Error: Object expected
Code: 0

I had some other problems with "Error on Page" after upgrading, but was able to get around many of them by doing "Repair Sugar" from the admin area.

Any ideas on what's going on and how to fix it?

[Angel]

There is another unresolved thread with a similar problem that's been floating around for a few days now.

Maybe you have some info that might lead to a solution.

Can you tell us more about your environment?

Server operation system:
Workstation OS:
PHP version

etc..

How did you perform the upgrade? Any error in that process? Any custom modules installed?

[esher]

I'm running my Sugar installation on Yahoo! web hosting over https. This led to some weirdness in the past because once it's in the ssl area, the URL of my installation changes from http://www.<mydomain>.com/ssl/crm to something like https://s.p10.hostingprod.com/@www.<mydomain>.com/ssl/crm/index.php?module=Home&action=index
However, as of 4.5.1 most of those issues were fixed and it was working nicely.

My site is running PHP 4.3.11; it seems to be running FreeBSD. As far as the upgrade goes, I just ran the upgrade wizard. The only custom module I had installed was a free Gantt chart module that was on SugarForge. I can remove that if it's causing problems, but it plugs into the Project module so I don't know why it would affect the Tasks area.

There were no error during the upgrade, but I did have some problems with the Leads and Contacts (error on page) until I went into the Admin area and ran "Repair->Quick Repair and Rebuild" with the default options. I tried that again for this problem but it did not seem to help this time.

Thanks for any ideas!