Default paper size scanning problem, LaserJet M1120n MFP

Question

Hi, I just got a used LaserJet M1120n MFP. Installed the most up-to-date drivers form HP's website. Printing is fine over USB or LAN, however the WIA scanning driver defaults to paper size "Letter" and I can't scan A4 pages all the way. The bottom is always cut off and I get an unwanted strip besides the scanned document. Please, advise how to change the default paper size of the WIA driver to A4. I use Windows XP Pro. Looked everywhere but cannot find any settings that will allow me to change the default paper size. Any ideas?
I have been thinking, could default paper size be somehow be tied to system locale? My locale is European and all other device drivers do default to A4. I wonder how the WIA scanning driver chose to default to Letter size.
The TWAIN driver works fine (I can choose default paper size), though it is less intuitive than I expected. Too bad I can't use it over a LAN. Is there a way to calibrate the scanner for white as the background seems kind of dark?
Your suggestions and ideas are most appreciated. Thank you.

Answer 1

Thanks for the reply, Spencer. I have used Adobe Acrobat to scan by means of the WIA driver, but when I do so the paper size selection box is dimmed (inactive) and I can't choose any paper size (nor any is preselected). I have also used Win XP's native Scanner and Camera Wizzard; it doesn't even have a paper size setting. Then I have used it with Win 7's native Windows Fax and Scan; no paper size setting here either.
Here is a useful thread on the same issue from Adobe's forum: http://forums.adobe.com/thread/844549
Reading around the forums I came across several posts where people discussed the impossibiity to set paper size when scanning using the WIA driver. Their problem was a bit different, though. The WIA driver had locked to size 'Legal' while they needed to scan in size 'Letter'.
The WIA interface was developed by Microsoft and here is what they have to say about the issue:
http://msdn.microsoft.com/en-us/library/windows/hardware/ff548440%28v=vs.85%29.aspx
'Supported Scanner Paper Sizes
Although two WIA user interface components are able to display a list of page sizes to the user, there is no easy way for a WIA driver to know which page sizes a scanner supports.
Page Size in WIA Applications
There are no WIA properties that allow WIA drivers to report supported page sizes or that allow applications to specify page size directly. To communicate page size settings to a driver, an application must calculate the required size in dots per inch (dpi) and adjust the origin of the scan to conform with the registration requirements of the device.
Page Size in the Common Scanner Dialog and in the Scanner and Camera Wizard
Both the Common Scanner Dialog and the Scanner and Camera Wizard have a static table of supported page sizes in which each page size is described by its horizontal width and vertical height, both in increments of 0.001 inch. These page sizes are currently displayed only when the scanner is in document feeder mode.
The largest page size (by area) that a driver supports in page feed mode, as determined by the maximum bed size, is considered the default page size. Paper sizes that do not fit on the feeder or on the bed of the device are not offered to the user.'  -- exactly my case!
Having tried the same WIA driver (developed by HP in this case) on several PC's running different WIndows OS and using non-US locale settings, I have came to the conclusion that HP may have hard coded the Letter paper size in the driver. I guess this works for North America but not in Europe where A4 is the standard size.
I guess I have to look into ways to get to that hard coded paper size setting in order to be able to make use of the driver. I don't even know if that will be possible but I'll keep on reading. Wish me luck