This program has performed an ilegal operation and will shut down,
followed by a noise: nyallk.  Same error message from: explorer, Mmsg,
Rundll32, Stimon, eanthology, systray,and others.

No other indication of what may have caused it? What program were you
running? What OS? Has this just recently started or been happening for
a while?

perhaps you have got a computer virus.
You need to scan your computer with a anti-virus software.
or you need to reinstall the operationg system .
it is recommanded to upgrade your system to a newer version.