Application Error in 9.05.701

Good morning all;

Once again I am looking for some feedback suggestions as to what could be causing the following error:

“Exception has been thrown by the target of an invocation”

This has been popping up at random (and not for everyone) upon opening a deployed updateable dashboard, which is of course using an updateable BAQ.
I have some Custom buttons on the grid that upon clicking execute some code.

Everything seems to be working fine, with the exception of this error occurring at random. Once we clear that person’s cache, the error disappears. Is there any way to prevent this error upfront from occurring?

Thanks much!
Carol