ERROR when running SSRS subscription (SQL Agent job)

Hi,

I have package, which in one of it's way runs few report subscriptions () from SSRS. It works on my machine from BIDS, but when I run it on server, it says error

Code: 0xC0014054     Source: Run SSRS subscription      Description: Failed to lock variable "RunId" for read access with error 0xC0010001"The variable cannot be found. This occurs when an attempt is made to retrieve a variable from the Variables collection on a container during execution of the package, and the variable is not there. The variable name may have changed or the variable is not being created."

Similar error is for other subscriptions, that are run by package.

Proxy User which run package has sysadmin rights.

Thanks a lot