Subscription of a report with subreport

Hello,

I have an SSRS report, which includes subreport. The report shows statistics for specified number of production machines, subreport shows statistics for one machine. When I want to create a standard subscription of the report, I get the error:

"Subscriptions cannot be created because the credentials used to run the report are not stored, or if a linked report, the link is no longer valid."

The main report and the subreport use data sources with stored credentials.

Any idea, where is the problem? Is it possible to subscribe a report containing a subreport?

Thanks in advance for any help.

MP.