Make sure the higher privileged application is the one changing the message filter of the lower privileged window. Ensure you have the correct window handle of the lower privileged window. Have a read through the remarks for ChangeWindowMessageFilterEx.
Another thing to be mindful of is if you allow multiple instances of the same application. You may need to consider using mutex's or assigning unique identifiers to each application...
didn’t mean to stir up arguments
1) I'm not signing into anything
2) not re-downloading vis studio
3) not paying
point was just to show how dumb MCSFT is that this ide should have expired and forced me to do any of the above prior 1-3’s, and all it takes is a simple clock setback to continue to use it despite its being expired without any license
ps: sure, I could vm my os and do it that way