There is a bug with supplied Riot plugin (v0.3.3.0) in irfanview 32 bit (I'm using the latest version).
How to reproduce the bugs:
1. Open any image file with irfanview.
2. In the menu, choose: File > Save for Web (plug-in)
3. On the "Save for Web" dialog, click the "Open..." or "Save" button. It would show the open/save dialog.
4. Click cancel button on the opened dialog, so the dialog will close and it will return to the "Save for Web" dialog.
5. At this point, make sure you don't do mouse left-click at anything, otherwise you have to repeat the step 3.
6. Now you would see the "Save for Web" dialog now becomes a modeless dialog, and the app focus is switched to the irfanview main window behind. At this point, if you press ESC key, the irfanview app will close, but if you check with task manager, the irfanview app process (i_view32.exe) is still running on the background. I guess that's because the Riot plugin ("save for web" dialog) isn't really terminated yet so that makes the irfanview process gets stuck.
Could you fix this bug and make a minor version update (something like 0.3.3.1) to the supplied Riot plugin for the irfanview, and then send the updated plugin to the irfanview author ?
I know I can just install the latest riot plugin for a solution, but other users out there mostly don't realize the "Save for web" dialog is actually coming from the 3rd party plugin (riot plugin) and would think this is irfanview's bug. So I think it's better if you can fix this bug.