Using 2 USB2 scanners with winXP

[chris.wilkinson]

I have run into trouble adding a USB2 film scanner to my computer.

I already have a USB2 flatbed scanner and have found that to use the
new film scanner I must disconnect the flatbed, plug in the film
scanner and reboot.

MS have a KB article on this problem (KB Article ID : 324756) in which
they say that this is the only workaround. The article is dated July
2002 and there does not seem to be any effort by MS to fix this
deficiency. The problem appears to be with the usbscan.sys driver. It
can only support one scanner/camera, 'grabs' the first one it finds and
can't be persuaded to let go.

I tried just disabling the flatbed in device manager but this does not
work. The film scanner then shows up as OK in device manager but
actually does not work.

The same problem occurs if I connect a digital camera via USB.

Has anyone found a way to avoid the need the unplug/reboot when
switching scanners?

 

[CSM1]

I have run into trouble adding a USB2 film scanner to my computer.

I already have a USB2 flatbed scanner and have found that to use the
new film scanner I must disconnect the flatbed, plug in the film
scanner and reboot.

MS have a KB article on this problem (KB Article ID : 324756) in which
they say that this is the only workaround. The article is dated July
2002 and there does not seem to be any effort by MS to fix this
deficiency. The problem appears to be with the usbscan.sys driver. It
can only support one scanner/camera, 'grabs' the first one it finds and
can't be persuaded to let go.

I tried just disabling the flatbed in device manager but this does not
work. The film scanner then shows up as OK in device manager but
actually does not work.

The same problem occurs if I connect a digital camera via USB.

Has anyone found a way to avoid the need the unplug/reboot when
switching scanners?

No. That is the way Microsoft designed USB.

You Cannot Simultaneously Use Multiple USB Scanners in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;324756

 

[Bruce Uttley]

[snip]

Has anyone found a way to avoid the need the unplug/reboot when
switching scanners?

No. That is the way Microsoft designed USB.

You Cannot Simultaneously Use Multiple USB Scanners in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;324756

I have been running Windows 2000 Pro with two USB scanners for
years. The Epson and Xerox scanner are both connected on USB2
ports and both are powered on. The scanner interface to both
is Twain. I have never tried to 'simultaneously' scan two images
into two running applications, but I can successfully switch
between the two scanners in applications like Omnipage, Photoshop
and the vendor supplied scanner apps without rebooting.

Would I not be able to continue to have my two USB scanners
connected to my system if I upgraded to Windows XP Pro? Or is
the key word here 'simultaneous' -- a use of scanners that I
would be unlikely to ever need?

Thanks for any insight into this 'feature' of Win XP.

 

[bmoag]

The TWAIN driver will not allow two scanners to be used simultaneously.
There is absolutely no limitation in any version of Windows to switching
between USB scanners: I do this daily with WinME and WinXP.
However there are conflicts between the USB port and other devices that want
to share the same IRQ and that may be what you are encountering.
There also may be an issue with the drivers for one of the scanners. Make
sure there are no settings checked that automatically activate the TWAIN
driver when the scanner is turned on. Make sure the first scanner driver has
completely terminated before trying to use the second: sometimes you have to
manually close the driver window.
If you computer has two USB ports first try making sure each scanner is
plugged into a different port; it should not mattter if you have a USB
switch box somewhere in the chain.
If that does not work or is not possible try adding another USB port with an
add-in PCI card.
A good source of information on USB problems is usbman.com.

 

[CSM1]

[snip]

Has anyone found a way to avoid the need the unplug/reboot when
switching scanners?

No. That is the way Microsoft designed USB.

You Cannot Simultaneously Use Multiple USB Scanners in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;324756

I have been running Windows 2000 Pro with two USB scanners for
years. The Epson and Xerox scanner are both connected on USB2
ports and both are powered on. The scanner interface to both
is Twain. I have never tried to 'simultaneously' scan two images
into two running applications, but I can successfully switch
between the two scanners in applications like Omnipage, Photoshop
and the vendor supplied scanner apps without rebooting.

Would I not be able to continue to have my two USB scanners
connected to my system if I upgraded to Windows XP Pro? Or is
the key word here 'simultaneous' -- a use of scanners that I
would be unlikely to ever need?

Thanks for any insight into this 'feature' of Win XP.

It does make a difference is you have two scanners connected to two
different ports.

As long as you do not have both scanners active at the same time, XP will
not know that a second scanner is connected.

The problem with XP, is it uses only one Usb driver. And it is not
reentrant. I think they made a change in SP2 with the USB drivers.

 

[Hecate]

The TWAIN driver will not allow two scanners to be used simultaneously.
There is absolutely no limitation in any version of Windows to switching
between USB scanners: I do this daily with WinME and WinXP.
However there are conflicts between the USB port and other devices that want
to share the same IRQ and that may be what you are encountering.
There also may be an issue with the drivers for one of the scanners. Make
sure there are no settings checked that automatically activate the TWAIN
driver when the scanner is turned on. Make sure the first scanner driver has
completely terminated before trying to use the second: sometimes you have to
manually close the driver window.
If you computer has two USB ports first try making sure each scanner is
plugged into a different port; it should not mattter if you have a USB
switch box somewhere in the chain.
If that does not work or is not possible try adding another USB port with an
add-in PCI card.
A good source of information on USB problems is usbman.com.

The simplest solution is not to use 2 USB scanners. I have one
connected via USB2 (a flatbed) an the other (a film scanner) connects
using IE1394.

 

[Steven Kefford]

The TWAIN driver will not allow two scanners to be used simultaneously.

.....

I was under the impression that XP does not use TWAIN. I thought it used
WIA, or whatever it's called.

Steve

 

[User 1]

....

I was under the impression that XP does not use TWAIN. I thought it used
WIA, or whatever it's called.

Steve

Steve asked a very important question here. Does anyone have any
helpful clarifications? Why are so many of the issues here regarding
scanners on Win XP discussed in terms of TWAIN (and why is there a
TWAIN_32 folder in Win XP) while at the same time various scanner tech
supports purport that XP uses only WIA?

Stan

 

[CSM1]

Steve asked a very important question here. Does anyone have any
helpful clarifications? Why are so many of the issues here regarding
scanners on Win XP discussed in terms of TWAIN (and why is there a
TWAIN_32 folder in Win XP) while at the same time various scanner tech
supports purport that XP uses only WIA?

Stan

Windows XP uses both.

If the Scanner manufacturer has a TWAIN driver, use that.
The manufacturer's TWAIN will support more features of the scanner.

Some manufacturers has discontinued support for their older scanners that
are supported with WIA.

If the older scanner is supported with the Windows XP WIA, you can use that.
Not all scanners are supported with WIA.

 

[User 1]

THANKS!

Windows XP uses both.

If the Scanner manufacturer has a TWAIN driver, use that.
The manufacturer's TWAIN will support more features of the scanner.

Some manufacturers has discontinued support for their older scanners that
are supported with WIA.

If the older scanner is supported with the Windows XP WIA, you can use that.
Not all scanners are supported with WIA.