VB Mail Control(編號:2266)

I have write a program which is used to compare two database with same structure and then write the compare
result to the text file and finanlly, use vb Mail control to email the text file.
The problem is when I run all the database (more than 1000 records), the program runs to the "mail1.action=connect" and
then without no action.
but, if it only run less records(20 records), it can email the text file.
So, I don't know what happen!
Hope that someone can help me! Thanks!