When upload packages to the IS server, can’t execute packages anymore

why?

It seems like a 64-bit issue. Some connection managers won’t work on this version. The following blog describes the same symptom I am facing now:

http://tsutha.blogspot.com/2006/05/getting-ssis-packages-to-run-on-64-bit.html

Seems it’s related to the ProtectionLevel under the security section of package property

Here is the detailed thread

http://social.msdn.microsoft.com/Forums/en/sqlintegrationservices/thread/1a7c23c8-5f4f-4891-981b-5e1f4e7d33fe