Ok, so I have a number of 32gb DataTraveler 100 G3 thumbdrives, they boot either WinPE 3 or 4, and using the HKEY_Local_MACHINE\SYSTEM\CurrentControlSet\Control\PEBootRamdiskSourceDrive" to find the assigned driver letter and change it to a fixed letter so we don't accidentally wipe the USB drive if the internal hard drive has no partitions.

 

So on some laptop machines if the power adapter is plugged in the referenced registry value is not created, even if you use "WPEUTIL UpdateBootInfo" to force the creation of it. If the machine is running off of battery it seems to always work fine, issue comes when the machine has a dead battery and can not be run without the power adapter.

 

Another interesting thing to note is that I have the same thumbdrive in an 8gb version and this issue does not happen with that drive.

 

Anyone see this before or have any idea, I've beat my head against it for three days now with no luck.

Another interesting thing to note is that I have the same thumbdrive in an 8gb version and this issue does not happen with that drive.

Interesting

And scary/queer.

Three questions:

1. Are both the 32 Gb and the 8 Gb set as "Removable" (or as "Fixed")? (or are they differently set?)
2. Are both the 32 Gb and the 8 Gb partitioned (or "superfloppy")? (or are they differently set?)
3. Have you tried making a smaller than 8 Gb partition on the 32 Gb stick? (if it is partitioned)

jaclaz

Additional:

4. Does this ever happen with desktops?

5. Have you tried it on a desktop with a card reader installed?

6. Does this happen if no battery is installed?

Also post the make/models of these notebooks. I may be able to do some testing as well.

1. Not sure, not an easy thing to check when booted to WinPE, but I will check that tomorrow, in PE and installed OS.

2. Both are partitioned using the same diskpart script:

Sel disk 4

clean

create part pri

sel part 1

active

format fs=ntfs quick

assign

    then the WinPE files are copied over.

3. No i have not I will attempt that in the morning also.

4. Never reported by anyone with desktops.

5. Yes, card reads have never been an issue.

6. I can try that tomorrow.

 

Thanks for the suggestions, this has been a fun one to track down.

Of all the 16GB and 32GB USB keys I've used (there isn't many, I prefer 1GB myself) they are always detected by normal Windows 7 as a DVD_ROM in Explorer.

Tough to fit a 16gb image file on a 1gb USB stick for offline imaging.

Tough to fit a 16gb image file on a 1gb USB stick for offline imaging.

Of course! I'm not saying you are using too large of USB keys, I'm saying that sometimes Windows detects a USB key as a CD or DVD rather than a removable disk.

Yeah, it has been so rare that it has been an issue for me I forgot about that.  Soon as I finish creating installers this morning I'm going to investigate this and the other items.

Well, it's the first time I hear that a USB stick can be detected as CD/DVD (unless it is set to be one on one or both it's LUN's, or it is a stupid U3 stick)

 

jaclaz

1. Both the 8 and 32 are detected as removable disk.

 

3. Different partition size on the 32gb drive, made no difference.

 

6. Makes no difference if the battery is removed, still does not work.

Another thing to check (though it is more like shooting in the dark ) do they have the same current consumption?

 

One of the "features" of USb devices is power consumption, maybe one has a lower value than the other?

Like one beiing - say 100 mA and the ther being - still say - 300 mA?

 

Try running this with both the 8 Gb and the 32 Gb connected and see if you can spot any difference (besides the obvious ones connected to size) :

http://www.nirsoft.net/utils/usb_devices_view.html

 

jaclaz 

USBView shows everything the same for both the 8 and 32 gb drive except size and serial number.

 

They are both 300 mA devices, which should not be an issue I have a 64gb thumb drive the tools says uses 498 mA and that drive works without issue but is a different flavor of Kingston drive from the other two.