Multiple value parameter not loading on server

Question

My problem is with the reporting services for sql2008:
-I add a parameter to an already established report, where I get the names of certain people. RespStep, and it shows on the preview. But when I upload it to the server, it wontshow: It pretends it´s loading for less than a second and then the report stays in blank.

NOTES:
This behavior happends only when I set the parameter to allow multiple value.
I thought it was a null problem, but the column from where the parameter values come has no nulls and still presents these problems.
I am desperate to know where the problem might be, on the server the data source and everything is well directed. Actually it shows no erros, just wont load anything and keep the page in blank.

Answer 1

just delete the report on server and re-depoly it.after that you can see the parameter in report