SSRS data driven subscription issues?

Hi,

i implemented data driven subscriptions for 2 reports with windows file share server Option.

Method:

in each report 200 users available and we are generating reports and moving to corresponding folders automatically with help of data driven subscription.

Issus:

1. in subscription i find the issue like :"200 processed of 200:18 errors" : this is for monday

2. for same report on tuesday i got the error like :"200 processed of 200:12 errors:" 

Note: i havn't made any changes in report and schedling also.

Requirement;

1.how do i find who are all the users not getting the reports. (or) how do i find where exactly error generated.

(In error log file there is no appropriate information and in subscription table i can able to find the same as above in status column i.e

200 processed of 200:12 errors)

2. out of 200 users 20 users have no data in reports . now how do i stop to export empty reports in subscription

for the above problem i saw the below link

http://blogs.msdn.com/b/bimusings/archive/2005/07/29/445080.aspx and i am confusing the below query of highleted

SELECT * from DataDrivenSubscriptionInfoTable
WHERE EXISTS(SELECT SomeField FROM TheDataSourceTable WHERE DateField Between DateAdd(dd,-3,GetDate()) and GetDate())

Note: what is data source table name here?

because i using procedure which contains the query of 15 tables joins so i cannot say what is exact data source table?

thanks in advance

franklinsentil