Trigger not firing in SQL Server 2000

Question

Hi All,
I have created a Insert Trigger and a Update Trigger on a table in a database in SQL Server 2000. The Insert trigger will make an insert into another table whenever an insert happens on the table on which trigger is created.
Now an external application (developed in .NET and I have no source code access) makes an insert successfully in the table. But the trigger doesn't fire.
When I directly execute a insert script on the table from SQL Query Analyzer, then the trigger fires but when insert is done by the external application (.NET app) the trigger doesn't fire.
Can somebody help me out with this...I'm completely clueless as to why it is behaving this way.
Thanks
Debsoft