Hi I'm a noob so bare with me here.
I'm actually not quite sure how I fixed this but for those interested I will detail my experience, perhaps something I did can help you too.
Two days ago I installed VMware Workstation 7 and Snow Leopard 10.6 on my XP running SP3. At first I appeared to have success but upon trying to connect my iphone I got error message re Arbitrator 4 error, could not find component on server etc...
Thinking it was my VMWare tools I figured out with help from threads how to mount my Darwin iso and run. Again, thought I had achieved success but no, same error.
The device was visible under VM->Removable Devices and it connected fine to the host. It even disconnected from the host when I selected connect. By now I was wondering if this is just a bug that has no solution yet (though some people appear to have found solutions none worked for me).
In desperation I thought, well I'll test my printer, I can see that device too. Same error, however this time I got a message about icuin36.dll which I of course downloaded and moved to the appropriate folder (somewhere in the system32 file I believe, google it, thousands of hits).
I then tried to connect my device again, this cause my computer to crash and gave me the blue screen of death.
I of course went into immediate panic mode as I use this computer for my work and was only able to backup selected files due to space restrictions.
Rebooted my computer, powered on my VM and tried again, no success.
Powered off VM, closed Workstation, reopened and powered on again, this time it prompts me to download 6 drivers (don't ask me what they were) which I did. Try again, was able to connect device successfully, however after disconnection it would not reconnect.
Power VM off and back on again. I next got a hint message about not being able to automatically connect to a device that has been previously connected and that I would have to manually connect. Clicked on the do not show again button and all is fine. When I plug my iphone in now it automatically connects to my XP, then in VM I can connect and disconnect it manually, over and over, it works perfectly. Voila, problem solved.
I have written this from the top of my head the day after so if I missed anything I apologise, but the meat of it is there and hopefully it will help another poor soul.
Good luck!
Note: It does take quite a while for my VM to pick up the connection so be patient, it might be an issue with my settings as things seem to run very slow (any ideas on that topic would be appreciated) in it but just in case, give it a minute or three to connect before you give up on it working.