The affected apps are Maxthon.exe (Maxthon 22.214.171.1240) and Azureus.exe (Azureus/Vuze 126.96.36.199), though I don't suspect them of having internal errors. That exact version of Maxthon (synched across multiple computers) runs on other machines with no problem, and the Azureus install was restored from another machine (although it has autoupdated a few times since.)
I've been Googling around and searching the forums, but I have yet to find any definitive cause. If anyone has brilliant ideas or things I can investigate, please share.
The machine in question runs WinXP Home SP2, 2.8GHz processor with 1GB of RAM. Antivirus is PC Tools' Spyware Doctor with AntiVirus (v188.8.131.52).
Here are my troubleshooting notes:
Sometimes Maxthon and Azureus have problems accessing the internet when both are run simulataneously — and not because of bandwidth congestion. I'll be able to ping web sites from the command line, but I can't pull up sites in Maxthon — the browser just spins, rarely even giving a 404 message.
Azureus will eventually stop downloading, as well, even if Maxthon isn't running. This usually takes a couple of hours, but sometimes it's quicker. Once active downloads have stopped, Azureus.exe typically remains in memory, resisting all attempts to kill it with Task Manager, SysInternals Process Explorer, or APT Advanced Process Termination.
On some occasions, I've been able to launch a second Azureus.exe process, which is able to download and upload as though the first process didn't exist. (!) At other times, I get an error message when the second Azureus launches, warning me that an application is already listening on the Azureus port. (I should've verified that it was the correct port, but I didn't think to check.)
Like Azureus, once Maxthon has started failing to load web pages, it will close but not disappear from running processes. Again, I can sometimes launch a second Maxthon process which runs side-by-side with the hung process without problems (and sometimes I do this unknowingly, having closed the first one for not responding and launced a second instance).
The longer these processes run, the more likely that a Windows Logoff or Shutdown will fail. I often have to force shutdown by powering down the machine.
CAUSES (possible) & TROUBLESHOOTING STEPS TAKEN
Spyware Doctor hadn't detected any problems, but a TrendMicro Housecall scan on 2008-04-22 turned up Java_ByteVer.A, Java_ByteVer.C, Java_ByteVer.S, and Java_ByteVer.AQ, as well as TROJ_GENERIC, all of which reported as successfully cleaned (in Safe Mode with Networking). I disabled System Restore after cleaning and before reboot (still in Safe Mode). A subsequent scan with Spyware Doctor (in Normal Mode) then detected (and cleaned) Adware.PodcastbarMini.
Housecall recommended this link with Microsoft Java Virtual Machine (JVM) patch details:
Checking for a JVM via command prompt » Jview turned up nothing installed. (?) Just to be safe, I uninstalled Java using Add/Remove Programs — and although I have yet to reinstall it the JRE, Azureus is working fine in testing. (??) (Confirmed the absence of JRE at Sun's Java test web site.)
Azureus locked up twice during testing on 2008-04-23, but once was after leaving it running overnight, and the entire PC seemed be locked up; the other time was in the evening, when I couldn't kill the task — although Maxthon ran successfully for a while afterward, and Windows had no problems shutting down.
I've also run HijackThis but found nothing especially suspicious, other than a few unusued (but perfectly legit) Roxio entries, the PrismXL deployment service remnant known to exist on eMachines/Gateways, and Viewpoint Media Player (grayware that comes with AOL Instant Messenger).
My registry had been tweaked to allow more than two simultaneous connections per server, but this is the case on other PCs that don't experience problems. (None of the others have Azureus installed, however.) Just to be safe, I reset the max connections to 2 (Microsoft's default).
Any brilliant ideas, insights, or similar symptoms welcomed!
Edited by Secret-HQ, 24 April 2008 - 02:41 PM.