I have two devices that require periodic downloads from the Mac via USB. One is a proprietary datacard writer for the database in a GPS navigator that requires about a 10 minute erase/download/verify sequence monthly. The other is a programmable remote for my home theater that requires frequent 60-second downloads if I am re-configuring it. The software for both of these runs fine under Parallels, and the devices are seen just fine when I plug in the USB connection. So, we're not dealing with the dreaded "device in use by another application" problem. (Been there. Done that.) The problem is that when I start a download with either of these devices, it only completes about 30-40% of the time. Most of the time, it freezes halfway though or stops the download with some sort of "communication error" message. I have a Boot Camp installation on the same Mac, and these downloads work about 90% of the time if I run them from Boot Camp. However, it would obviously be much more convenient to have them run reliably under Parallels. Is there some sort of Parallels or MacOS setting I'm overlooking that might fix this? Configuration details: Parallels 3.0 build 5584.0 with Windows XP pro vers. 2002 SP 2. MacBook Pro with 2.16ghz Intel Core 2 duo running OS 10.4.11.
Similar Erratic USB I'm using a 2778 USB network connection box to run a digital xray software program capture device. Like yourself, initially the device works fine, but it seems to 'time out' after a certain period. My guest OS (Windows XP SP2) seems to forget that the device is attached, (or maybe the Mac is trying to steal it away...not sure what's happening.) If I deselect the USB device from the Parallels menu and then reselect the USB item, it works again only to time out again a few minutes later. (This software and device works fine on a regular windows machine .) I'm using the latest Parallels Desktop 5608 and Leopard 10.5.3 on a new Penryn MacBook with 2 gigs memory. My guest OS is Windows XP SP2. I've posted a similar issue with email support. It's been a week and I haven't received any response.
Sounds identical to my problem. I never heard from support either, but eventually came up with 2 fixes: First, as I said in my initial post, I installed Boot Camp, and sure enough the USB downloads worked fine. Later, I downloaded and installed VMWorks Fusion (you can try it free for 30 days.) They advertise USB2 support as one of their advantages, and they were right. Running Fusion using my existing Boot Camp partition, all the USB connections worked perfectly. The installation is definitely not as user-friendly as Parallels, but once you get it up and running, it feels very solid and speedy. If it works for you, you can buy a permanent copy on Amazon for $60, which comes with a $20 rebate ($30 if you can prove ownership of Parallels or Virtual PC)
