Phex, which is definitely my favourite gnutella client, unfortunately doesn't work stable anymore in the 0.5.x versions. I can absolutely reproduce this error. It always appears when a search query returns a big amount of files (i can't tell where the limit is, but whenever I get just a few returns, it works fine).
If Phex crashes, all you can see is an empty window that can't be shut the normal way.

At the moment I'm using Phex on a machine with a 1 GHz AMD processor, 192 MB of RAM and a Windows ME environment. The problem is that I have recently changed this. Before I was using Phex 0.4.6 on a 500 Mhz Pentium II and Win 98 with the same amount of RAM. Thus, a hardware problem cannot be excluded, although I rather suspect a bug in Phex.
I hope this can be fixed soon.
Question: Is there a version of Phex older than 0.5.0 still available on the net?