IsoBuster closes automatically when infected with a virus.
Did you know that IsoBuster checks itself, each time you start it ?
If a virus attaches itself to IsoBuster on your system, because your system got infected somehow, then IsoBuster will close automatically the moment that you try to run it.
In the next version (> 1.9.0.3), IsoBuster will alert you with an appropriate error message before it shuts down, so that you can take appropriate action and scan your system.
While on topic, talking about viruses, always make sure that you download IsoBuster from a trusted source. Therefore best download starting from this very website: /
download
/ and best not download from dodgy sites.
This way you get to download verified downloads. E.g. verified by: