E_RPC_ServerFault exception when i am querying SDEFeatureClass

Question

I am querying 100 SdeFeatureclasses Inside a for loop using a Polygon using following code.

//This List of SDE.FeatureClases.. List FeatureClassList=GetFeatureClasses();
Code:

'for(int i=0;i<FeatureClassList.Count;i++){

ISpatialFilter pspQuery=new SpatialFilterClass();
pspQuery.Geometry=myGeom;
pspQuery.spatialRel=esriSpatialRelEnum.SpatilRelIntersects;    
PFeatureClass=PworkSpacefactory.OpenFeatureClass(FeatureClassList[i])    
int Count=PFeatureClass.FeatureCount(pspQuery);

}'

When Query Reaches to 25th FeatureClass it, is showing E_RPC_SERVERFAULT Exception...... Do i have to Change any configuration settings in sde connection files. Here i am using PropertySetCLass Only.....

ThankS SRI