event receiver not firing event after multiple documents uploaded into document library in item updated event

I have an event receiver.On item updated event i am firing email.condition is like this: I have an document library with two Yes/No columns(i.e Notification & IsActive).If both these conditions are true ,then email will trigger.Its working fine.On item adding event i am changing value of IsActive column to false.It is also working fine.But when I am uploading multiple documents to document library email is not triggerring.I debugged and saw that debugger is not going to the send mail method.If any body knows pls guide.