May be somebody will help me out.
There is a scheduled report and it works fine on development server. I can schedule and review the history. it works.
Then I've exported the report using Wizard to biar file and imported into another server.
When I'm trying to view History of scheduled reports it shows the following message 'An error has occurred: java.lang.NullPointerException'. Meanwhile, it looks like the report was run because time-stamp is updated and the number of report instances > 0.
Any idea what is going on?