Parameters Values Are Not Saving

[ipmurali]

One of our reports having 5 parameters, they are accepting on the prompt page. When we run the report, instead of waiting the report to display on screen we usually give the option to mail the report, and it was working fine. But now when we run the report it runs with default parameters, not with given parameters. I checked the run history of the report, there I am seeing No value has been saved for this parameter instead of the parameter value. (It was showing the values we given in the prompt page)
Cognos 8.2 version on Windows 2003 server. MSSQL server 2005.

Appreciate your help !