Possible to write protect a disk/partition on boot up ?

I've ended up becoming the installer/updater/fixer for all my friends/neighbours/relatives computers. I have GENA & Win7PESE on a UFD - booted using grub4dos. The prob I always face is the UFD might get infected when used on someone elses computer. I came across this :
http://hackingexposedcomputerforensicsblog.blogspot.in/2014/02/daily-blog-242-how-to-build-winfe-to.html

I'm wondering if it's possible to have Win7PESE ( or Win8PESE ) write protect the boot medium ( in my case the UFD ) on boot up. Either have the user manually select the drive to write protect or maybe search for a tag file and write protect drive/s that have that tag file. Actually I would not even mind if the UFD is "ejected/uninstalled" on boot up.

Hi

This is the exact reason why i prefer CD over USB even though the boot time is higher. Any software write protection can be easily bypassed by malwares so i would suggest getting a UFD with hardware write protect switch.

An example - http://www.ebay.com/itm/PQI-Nano-32GB-32G-USB-3-0-Flash-Thumb-Drive-Disk-Write-Protected-Switch-Silver-/150992969736

Hi gbrao,

I fully agree with anshad 

ps: @anshad, do you use one of them,
 I could not find such switchable ufd around here,
  besides I will buy one in future 
    it is always better to follow experience of friends on such hardwares 




In addition:
your ufd should not get virus etc. when you boot SE from ufd ,
 you should be carelful about things you doubleclick 


Still,
+
about winfe, it is only about a nt6x feature which, nothing specially forensic,
Win..SE\\Finals\"Optimization" ==> There is "Don't mount local harddrives" feature
after that, after booting pe
you can use diskpart command to mount disk readonly .
or
you can use disk diagnostic utilities to check disks ( I feel without mount  )

ps: for such usage, use Build\"CdDrive - X: - Y:" --> Run All from Ram option



+
There is
Gena\Adjunct\"WriteProtectUSB_DaveXP"
plugin available, Better one check with SE to see if it works there 
If works, It seems to be the best solution you are looking for 

ps: @anshad, do you use one of them,

I had one sometimes ago but that one is not working anymore  . Pricing is the main issue for me. We need to pay almost triple or quadruple when compared to a a standard UFD.