.NET add-in Win Form changed to modeless after execution

Discussion created by xyknewtry on May 14, 2014
The form was launched via ShowDialog().

After clicking a button on it to execute a function, and while the form is still open, I noticed I can interact with ArcMap (remove layers, open layer attribute table etc.)

Just wonder if anyone has had similar experience, and what could have triggered this behavior.

Sorry I'm not allowed to post the code, but it executes a bunch of geoprocessing tools ("update" etc.) through the Geoprocessor.

I'm on ArcGIS 10.0 SP4, windows 7 64-bit.