Need help unrooting my droid pro to install update

[Stephinee]

Hi..Ive tried a number of times to unroot with Petes Motorla Tools, which is how I rooted, but I keep getting an error msg everytime I try. Im kind of phone stupid so I just cant figure it out. I know I can brick my phone but at this point I dont even care, I need to unroot! Thanks for any help.