Adobe strongly suggests that you use WIA support for your device, if available. If your device does not support WIA drivers, then try updating your TWAIN driver. Contact the manufacturer of your device for further TWAIN support.
To install the legacy TWAIN plug-in for Windows (32 bit), copy twain_32.8ba from:
C:\Program Files\Adobe\Photoshop Elements \Optional Plug-Ins\Import-Export\
C:\Program Files\Adobe\Photoshop Elements \Locales\\Plug-Ins\Import-Export\
Photoshop Elements version 9 and 10 is 32-bit applications. When installed on a 64-bit version of Windows, the path is slightly modified.
To install the legacy TWAIN plug-in for Windows, copy twain_32.8ba from:
C:\Program Files (x86)\Adobe\Photoshop Elements\Optional Plug-Ins\Import-Export\
C:\Program Files (x86)\Adobe\Photoshop Elements \Locales\\Plug-Ins\Import-Export\
The parameter <locale> in the path represents the name of a folder that varies based on your region and the language version of Photoshop Elements you install. Make sure that there is only one folder within Locales; it is two-digit language abbreviation followed with a two-digit country code. For example, if you install the North American English version, the folder is called "en_US" (English United States).
The parameter <version number> represents the version of photoshop elements you installed. If you installed Photoshop Elements 10, for your system is C:\Program Files (x86)\Adobe\Photoshop Elements 10\Optional Plug-Ins\Import-Export\