Cannot create a Data-driven subscription on a report

For an existing report in SQL 2008 R2 I want to create a Data-driven subscription, but in the report management, under subscriptions there is a warning sign along the button to create a data-driven subscription

• The report credentials are stored to run the report
• It is not a linked report
• There are no user-defined parameter values

But I found a message in the reporting services forums stating that the report might contain expressions depending on user like User!UserID

When I looked in the footer of the report there was indeed a text box with the page and the text “printed by “ User!UserID

After removal of this expression, the option to create a data-driven subscription was available.