OK guys you have obviously tried to root your pendo pad and failed or attempted to flash. either way you do not need an update.img file for it. Here is a quick tutorial how to factory reset your pendo pad. This will only work on windows since that is the only way i know how, but it should be basically the same for windows and mac.
First you are going to need Android SDK which you can just google android SDK should be first link
When installing it install it to an easy path E.G C:\ would be easier.
now once this is installed you now need to find where you installed it to and open SDK manager
you will then need to download Android SDK platform tools and android sdk tools also android 2.1 SDK platform in the android 2.1 drop down menu.
Once all of those components are installed and ready to use you need to set your environmental variables.
(windows 7 & vista) Go to computer and click system properties in the top tool bar, then click advanced system settings then a window will pop up and click environmental variables.
now in the bottom half where it says system variables find where it says PATH and change the path of it to where ever you downloaded the android SDK tools. for example if you installed it in c:\ change the path to "C:\android-sdk\platform-tools\adb.exe"
Once you have completed this you will need super1click rooting software which you can just google super 1 click download. try get the latest version 2.3.1 i think its by shortfuse or something
once downloaded extract where ever desktop would be easiest. then open up superoneclick application plug in your pendo pad via usb and turn on, hopefully you havent screwed the ADB drivers. now once plugged in and turned on open up super one click and click on Shell root. once completed, (it may crash upon completion) if so just close it hopefully it worked.
now for the final and easy step, open up your command prompt by clicking start and typing CMD into the search bar and pressing enter or for Windows XP press start click run and type CMD.
In the command prompt you need to type in adb shell
it will now say something about a daemon server starting or adb server stopping just let it go, once it finishes it should have a # symbol there, if it has a $ symbol do the super one click step again. if it did work and you have a # symbol simpily type "wipe data" without quotation marks, your pendo pad should reboot into factory default mode. (this may take a while to boot up). and enjoy