Named pipe error occurred:

Hi Experts,

I have received the following error during extract the data from MS SQL server 2008 R2 , i am using BODS 4.0 SP3:

Named pipe error occurred: <The pipe has been ended.>

Sometimes this error not appeared and the ETL job works fine and sometimes it appears.but i have to run the ETL job again and again.   

So , please help me to solve this error.

Thanks all.