CRM Application not working after CRM and Portal Upgrade

Hello All,

I have problem in upgradign portal and CRM.

After upgrading CRM from Support pack 6 to 10 we are unable to access some of the applications form Portal.

When I click on Activities link on the portal it says Page Cannot be dispalyed.

We thougth Portal upgrade can resolve the issue and upgraded portal from EP7 sp9 to SP 12 but it did not help.

Any clue where we went wrong .Are there are post upgrade steps that needs to be followed?

Regards,