Please refer to my detailed article. Most of the time, this issue will come due to insufficient RAM (less than 512 Mb) in WDS Client.
To all people starting with WDS, I really really want to warn in LOUD that please do care about RAM requirements as WDS could run if RAM is lesser in Server side, but it can’t if client is having less than 512 MB RAM. Now, after noticing this issue, I am finding that most of the issues, while implementation phase came for this single reason only.
Another thing, which I noticed is that any of the image, boot.vim or WinPE.vim could be used to capture or deploy, the objective of keep two images in the menu, make the two tasks seperate; One capturing image and second deploying image. With two images in menu, both the tasks may go together in production.
I also noticed that even if you might have created image for someone other HAL, sometimes it might work for other HAL (for me HP DX2280 image worked for IBM ThinkCenter), although drivers will still be missing. I thought one go around that collect RAW network drivers of all kind of machines you have (or as many network drivers, you can collect) in one folder and keep this folder in C:\ drive of every machine, you are going to image. It wont take many of Mbs, but will be handy, if you don’t have exact image, but a working image. At least you will easily get a network enabled, necessary software containing workstation, in which rest of the drivers could be filled.