I know there have been a number of users who haven't been able to get root again after the March 2, 2012 update.
Here are the instructions:
1) Download the package ZergRush-forKobo.zip
2) Extract the files from the package
3) Make a new folder in your user profile ( %USERPROFILE% ) and call it .android
4) Copy the file adb_usb.ini to the new .android folder
5) On the Kobo: Turn on USB Debugging under the development options
6) Connect the Kobo to the Windows PC
7) Go into Device Manager, and double-click on the K080 device, it should be listed under unknown. Choose "Update Driver" and pick "Let me choose a driver for this device", point it to the usb_driver package (in my instance I extracted the package to C:\temp, so my full path name was C:\temp\ZergRush-forKobo\usb_driver ). A list of devices will appear, choose ADB Interface
8) Restart the computer
9) Open up the zergrush runme.bat script and let it do it's magic, in my instance it was C:\temp\ZergRush-forKobo\zergrush\runme.bat
10) Install OogleVox
If you are having problems with the driver installation, I have included some scripts in my ZergRush-forKobo zip.
On XP, please try running uninstalldriver_xp.cmd this should clear out the Kobo specific driver for you. If you are still having troubles after the script, delete the infcache.1 file in c:\windows\inf ( you need to enable hidden files in windows to see the file). UNDER NO CIRCUMSTANCES IN WINDOWS VISTA OR WINDOWS 7 DELETE INFCACHE.1. Windows XP will automatically recreate the file, Vista and higher will not.
On Windows Vista or Windows 7 (or higher), please use uninstalldriver_win7.cmd to clear our the specific driver for you.
Both scripts require administrative rights. Once you have run the script, please restart your computer before proceeding with step 6 again.
This IS a new version of the download that contains these new script, please use this new zip instead of the old one.
03/11/2012, 10:47PM EDT:
I've updated the uninstall script for Windows 7 and included the modded version of the USB driver (as a different folder) in the package. If you are having troubles with the original USB driver, try the usb_driver_modded instead.
03/12/2012, 10:52AM EDT:
I've taken a video of how to "force install" the driver for those who are wondering, you can view it here: