Pocket PC USB
Connection Issues - Insights, Procedures & Tips from Microsoft
Most Pocket PC (PPC) users find that making a connection between their PPC and their desktop or laptop PC via ActiveSync works very well, it's a happy lot. However, there are some (very small in terms of %, but still significant in terms of number of users looking for help) PPC users that experience problems and must use extra procedures to accomplish a connection. Then, there are the rare (in terms of %) cases where the PPC user reports that they simply cannot connect no matter what they do, ouch! What's going on? Why is there such a wide variation in experience?
Microsoft's Derek Brown, who maintains an active presence in the microsoft.public.pocketpc newsgroup, recently posted some information that will be of special interest to those experiencing Pocket PC connection issues, and those wanting to understand these issues so they can anticipate potential problems, and perhaps avoid them altogether.
If you are having ActiveSync problems, please read carefully and take notice of any procedure or tip that you might violate, as this could be the source of your problem. For example, Microsoft states "… problems can crop up again by doing things like leaving the Pocket PC in the cradle during a PC re-boot, syncing two devices at once, etc." and "Don't reboot with a Pocket PC connected to the desktop via any connection method - Infrared, Serial, USB or Ethernet." These tips and others are given, in addition to some procedures.
In the Setup section take notice where it says that when installing ActiveSync, the order that components are introduced is important for a good install. Introducing components in the wrong order can cause problems that necessitate a "clean" reinstall procedure. In other words, simply uninstalling and reinstalling ActiveSync is not sufficient if there are underlying problems caused by a bad install procedure. Microsoft provides some instruction on cleaning up USB entries in Device Manager. However, you might also want to checkout Compaq's "clean" ActiveSync install procedure, which provides detailed step-by-step instructions and provides a deeper cleaning. See procedure 3b in this article: Top Connection Issues with iPAQ Pocket PC, Plus Recommended Procedures.
Posted by: Derek Brown, Microsoft, October 11, 2000, Newsgroup: microsoft.public.pocketpc
At the present time we think USB issues fall into three high level groups:
1. Setup - these are issues that can be corrected with a proper set up and procedures. Sometimes an uninstall of ActiveSync, deleting the USB devices and restart of both PC and Pocket PC are required. Then installing in the proper order - Start Up, ActiveSync, Connect USB, Insert Pocket PC. These problems can crop up again by doing things like leaving the Pocket PC if the cradle during a PC re-boot, syncing two devices at once, etc. This category we consider fixable with proper procedures.
2. Intermittent Sync Issues - This is the toughest of the three to track down. To some extent they may be caused from the above or more complex system setup. For instance on my system I have a laptop, docking station (which is USB hub 1), powered hub and a keyboard pass-through hub. I have an intermittent sync issue if I try to run both my iPAQ and Jornada off the powered hub (sometimes doesn't sync, unsafe device removal messages, etc.). If I put the iPAQ in the 2nd USB port on the docking station instead of the hub, things work fine. I know that you're supposed to be able to daisy chain USB forever but if you're having problems try cutting down on the variables. There may be ActiveSync issues involved here, there are variables with different OS versions, hardware, firmware, etc. We're working hard to break everything we see down and understand better. Will communicate more as we have info and solutions.
3. Total Fail - There are issues that prevent USB syncing at all. We think this has to do with some USB controller boards and/or hubs (this does not seem to be as simple as one controller type works and the other does not). These seem to be more prevalent with the iPAQs. The manufacturers do provide their own USB drivers so it is possible that problems could be on one Pocket PC and not others. While we're working on this suggested solutions are below plus try serial sync and removing hubs whenever possible.
Below are some procedures & tips that might help some of you.
1) Soft reset the Pocket PC before putting it in the cradle to connect.
2) Connect directly to the USB port on the PC. DO NOT go through any down level USB hubs, even if they are powered. Disconnect all other USB devices, if possible. Note: This only applies if you are having connectivity problems. Many people use hubs and other USB devices and never have any problems.
3a) Go into Connection Settings and disable "Allow USB Connection." Close out of the Connection Settings window, then reopen it. Re-enable "Allow USB Connection" and try to connect again. This is clumsy, but should reset wcesmgr.exe.
3b) Alternatively, you could use Task Manager to kill wcesmgr.exe and then manually launch ActiveSync from Programs or the Desktop before connecting.
4) Open Device Manager and then drop the device into the cradle. Watch Device Manager. If you see "Unknown USB" or "USB Device" show up in the tree, highlight it and then choose "Remove". Then reboot the desktop system and soft reset the iPAQ. Wait until the desktop has finished booting and then try to connect the iPAQ. (Note, USB Device may show up under your USB controller or it may show up under "Other Devices" in Device Manager.)
5) Remove any ghosted USB devices in Safe Mode.
6) Uninstall and then Reinstall ActiveSync 3.1, build 9587 [Build 9587 is the latest release as of this writing. The latest build is available for download from PocketPC.com]
- Make sure you are running the most current version of ActiveSync 3.1 build 9587, see above for download link.
- Make sure you have the most current BIOS updates for your motherboard. Out of date USB firmware can cause connections to be unreliable.
- Check with your desktop OEM (the company that built your PC, not Microsoft) to make sure that you have all available software updates for the hardware (aka. device drivers) on your system, including OS updates.
- Don't reboot with a Pocket PC connected to the desktop via any connection method - Infrared, Serial, USB or Ethernet. More about this in Setup above.
- Don't have more than one mobile device (Pocket PC, Handheld PC, etc.) connected to the desktop at a time. Having more than one serial cable/cradle or USB cable/cradle connected to the PC simultaneously is OK. Having multiple devices connected to these cradles simultaneously is not. For example, I can have the USB cradles for my Jornada 545 and IPAQ connected directly to my PC at the same time with out any problems. However, I can only plug one of the devices into a cradle at a time. If I plug a second device while the first is still connected, all bets are off.
A common scenario for devices with cradles is to drop them into the cradle to charge. If you have to charge a 2nd device while another one is connected, remove the AC cord from the cradle of the 2nd and plug it directly into the 2nd device so it can recharge outside the cradle. If the AC cord doesn't disconnect from the 2nd cradle, disconnect the 2nd cradle from the desktop until you are done using the other device.
IPAQ Problems. No single cause, but a combination of variables…
Compaq Support: "Issue #3: The iPAQ H3600 series USB cradle uses a UHCI (Universal Host Control Interface) USB. Some units use the less common OHCI (Open Host Control Interface.) We cannot guarantee that the iPAQ will work flawlessly when connected to a machine using OHCI. Normally it will recognize that you connected a device to it but it just shows up as an "Unknown Device." This is the same issue seen with many USB devices. Although a UHCI USB controller is preferred, remember the iPAQ WILL synchronize with some OHCI equipped hosts. To resolve this, try the following:...". (Source: Top Connection Issues with iPAQ Pocket PC, Plus Recommended Procedures)
The note covered in Compaq's Issue #3 above is incorrect. At face value, this sounds really plausible. However, I have spoken with COMPAQ development concerning this and they have verified that there is no such limitation. Also, I requested that Compaq have their support organization quit giving out this false information. This is an urban tech support myth that won't die. <g>
Our investigation so far has revealed that the problems don't seem to be caused by any one type of controller. Instead, combinations of the following are all variables that contribute to the problem:
- Motherboard & BIOS revision (specifically
firmware updates for USB)
The function drivers on the device and the host driver on the desktop are the only constants. Combinations of the variables above all contribute to throw the timing off, i.e. it only happens under certain combinations. This is why certain controllers work for some users but fail for others.
Do other Pocket PCs have issues too?
As far as other devices besides the IPAQ running into these problems? I've heard people complaining that their HP Jornada's have "some" of the same problems. My feeling and experience so far is that with one exception, all of the USB sync problems encountered by non IPAQ devices can be resolved by standard USB troubleshooting steps. Instead of making sure that they have the proper OS and BIOS updates, people want to jump to the conclusion that their devices are having the same problems the iPAQ is.
The one exception is if the device is powered off while in the cradle and then powered back on. This may hang sync in some scenarios. When we have more info on this, we will make sure it is posted on PocketPC.com and that the MVPs know about it before hand.