error with assebly

On preview custom assebly returns correct value - works OK, but on server i get an error like "#Error". Is it possible to debug report on server?
Thanks.Your custom assembly may not have permissions to do what you want it to do.
You'll need to edit the rssrvpolicy.config file and give it appropriate
permissions. Check
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/RSPROG/htm/rsp_prog_rdl_8mue.asp.
--
Ravi Mumulla (Microsoft)
SQL Server Reporting Services
This posting is provided "AS IS" with no warranties, and confers no rights.
<AG>; "NLB d.d." <AGNLBdd@.discussions.microsoft.com> wrote in message
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> On preview custom assebly returns correct value - works OK, but on server
i get an error like "#Error". Is it possible to debug report on server?
> Thanks.
>