[Jason Dunn]

I haven't seen this problem myself, but it certainly sounds like it could be common enough to affect many of your systems. David Topps had a message I thought was worth passing along:

"We have had a lot of trouble trying to get USB charge & sync cables to work with our iPAQs and some laptops. We have tried cables from several different manufacturers with same results in each case. The problem only seems to plague certain laptops but is absent for most - Toshiba and some Dell laptops seem to be most affected. The cable makers deny problems when they have done testing. It has been a very frustrating situation, especially since many of our traveling staff would dearly love not to lug cradles and power bricks for the iPAQ with them on the road."<!>

"I think I figured out what the problem is! What happens is that under certain circumstances, (most often when first connecting) there is a mild power surge and the iPAQ demands too much current from the USB port. As a protective response, the laptop disables the USB port and takes it off the list of available hardware devices. This is why uninstalling and reinstalling the USB port temporarily fixes the problem. Because the operating system thinks the USB port is no longer there, it fairly messes things up for other apps. However, the charge light still goes on for the iPAQ because Windows is not capable of physically shutting down that part of USB functionality.

This also explains why the cable works at first but then not after a few attempts and it explains why it only happens for some laptops. Some are more tolerant of the current drain on the USB port while others are not. Although the Charge n Sync was working at first, it would just have been a matter of time before it would have triggered such an action i.e. it was not specific to any particular cable or device connecting. Interestingly under Windows XP, the error messages are much more informative and give you the choice of disabling that port or not.

If you always turn off the backlight prior to connecting the iPAQ to the cable, this might help to some degree but I have found that even if I turn the backlight off, sometimes it turns back on again when ActiveSync first fires up. I reckon that this little problem has been troubling a few people out there so I thought that this might be worth posting."

[Jason Dunn]

I haven't seen this problem myself, but it certainly sounds like it could be common enough to affect many of your systems. David Topps had a message I thought was worth passing along:

"We have had a lot of trouble trying to get USB charge & sync cables to work with our iPAQs and some laptops. We have tried cables from several different manufacturers with same results in each case. The problem only seems to plague certain laptops but is absent for most - Toshiba and some Dell laptops seem to be most affected. The cable makers deny problems when they have done testing. It has been a very frustrating situation, especially since many of our traveling staff would dearly love not to lug cradles and power bricks for the iPAQ with them on the road."<!>

"I think I figured out what the problem is! What happens is that under certain circumstances, (most often when first connecting) there is a mild power surge and the iPAQ demands too much current from the USB port. As a protective response, the laptop disables the USB port and takes it off the list of available hardware devices. This is why uninstalling and reinstalling the USB port temporarily fixes the problem. Because the operating system thinks the USB port is no longer there, it fairly messes things up for other apps. However, the charge light still goes on for the iPAQ because Windows is not capable of physically shutting down that part of USB functionality.

This also explains why the cable works at first but then not after a few attempts and it explains why it only happens for some laptops. Some are more tolerant of the current drain on the USB port while others are not. Although the Charge n Sync was working at first, it would just have been a matter of time before it would have triggered such an action i.e. it was not specific to any particular cable or device connecting. Interestingly under Windows XP, the error messages are much more informative and give you the choice of disabling that port or not.

If you always turn off the backlight prior to connecting the iPAQ to the cable, this might help to some degree but I have found that even if I turn the backlight off, sometimes it turns back on again when ActiveSync first fires up. I reckon that this little problem has been troubling a few people out there so I thought that this might be worth posting."

[lee337]

I guess its not just me!

I have this problem with my Toshiba SatellitePro 6000 and my iPaq 3635.

The sync/charge cable works fine however with the HP Omnibook XE3 I use at work.

Lee J.

[carphead]

Had exactly the same problem with a Tecra 8100 and a H3630 but I also had the same problem using a Ericsson Phone and the same laptop.

But I don't have the same problem with the replacement IBM T23 laptop.

[johnm]

Mine has been working fine with my Compaq Presario laptop. My guess is that some of the laptop manufacturers have skimped on the power output for their USB devices.

[charlie]

a few people who have done the ipaq cradle usb power mod have emailed me about the same problem. blame it on the usb port. for desktop use you could always get a usb hub with an external power supply but that would defeat the whole point of not carrying around extra stuff.

charlie

[mvoosten]

Toshiba 8000's have the problem with 3630.
Ipaq 3850 works fine though

[JonnoB]

It is not a cable problem... it is a problem with the USB port not carrying full power.

[Sven]

Originally Posted by JonnoB

It is not a cable problem... it is a problem with the USB port not carrying full power.

I'm not sure it is a matter of it not carrying full power. Isn't the power spec for a USB port 500ma? That is .5A. What does a PPC with backlight on, playing MP3s at full blast and tryng to charge a 10% battery draw? There is probably a reason the chargers are rated about 2A.

I think it is more that some laptop manufacturers are giving more than required.

[JonnoB]

Originally Posted by Sven

I'm not sure it is a matter of it not carrying full power. Isn't the power spec for a USB port 500ma? That is .5A. What does a PPC with backlight on, playing MP3s at full blast and tryng to charge a 10% battery draw? There is probably a reason the chargers are rated about 2A.

I think it is more that some laptop manufacturers are giving more than required.

Some have 'shared' power... so if you are using a webcam, scanner, modem, or something else that is not self-powered but draws significant juice, you will often find problems with subsequent devices. If however, you plug in a fall-over hub that is per-port powered, all of the devices work off the same master that failed. Anyway, there is really nothing that can be done from the cable manufacturer standpoint.

[ChrisD]

I've seen this as well. I suspect that it's a power problem.

Yes the USB definition is for 500 mA and some units do provide more than 500 mA.

So if you go into the Control Panel - System on the PC and look at the USB host, you can see the power draw of the devices attached via usb.

My personal experience is that my Fiva MPC-206e notebook won't charge my iPAQ however my Intel 815EEAL motherboard will if I plug it in direct. If I use a USB keyboard with a hub, I can't plug in the iPAQ to charge into it.