What system are you on? Xp? Win 7? You're using the full sbf file? Also, make sure you're using a 2.0 USB port (sounds silly, but i ran into an issue myself because of this)
well as for me.. i have about 5 times and whenever i choose my SBF in RSD it dosent show in properties.. and also i get my phone in bootloader mode and connect it to RSD and it dosent show.. ive tried the option 'first come first serve' and ' automatically detect phone' and still nothing.. i have a droidX on stock GB and trying to SBF back to froyo so i can install the rootted version of GB. ive tried RSD lite v4.8 and v.4.9 any help!!
im on vista and i think so.. i got my SBF file from this video.. its one of those links in the desciption of this video [video=youtube;lEKH1jFMTJI]http://www.youtube.com/watch?v=lEKH1jFMTJI]YouTube - Part 1 of 2: How to Install Official Build of Gingerbread .596 (Rooted) on Droid X‏[/video]
The sbf file is extracted right? Rsd won't read a zipped file. Your phone should be in bootloader before plugging in and if you're using win 7 (or maybe even vista?) You'll need to run rsd as administrator. Make sure your drivers are updated as well From the motorola site