Cant Activate 8.1 Pro on new PC

Question

Hi Technet 
I recently bought a new toshiba notebook which came preinstalled with windows 8 standard, i am trying to do a clean install of window 8.1pro but even though my key will work on install, when i get to activation screen it shows the wrong product ID and in
turn will not allow me to activate.. I called MS and they confirmed i have a legit Valid windows 8.1pro key but their support department is closed until monday and i am trying to get this solved before then if possible..
unlike others who have had similar problems, for me when i install 8.1 pro it actually installs 8.1 pro, but i think its installing it with my bios key i am not sure..  
I have tried creating a usb install and then replaced the install.wim file with one that is meant to ignore the bios key but that didnt help, the phone activation numbers were still the same as the ones that originally failed and the product ID was still
wrong..
does anyone have a solution please, i would really like to use my pc asap and not have to wait until monday..
thanks
Huss

Answer 1

Hi Kelvin MS was a big waste of time, even though they had confirmed my key was valid & they tried to remote login and help, honestly they had no idea were to go on my pc, he logged in did nothing then logged out, later after they transferred me to
another section, they asked for my number & email in case they need to ring back. as they failed  to activate, i dont know but they must of realized i had a dreamspark account with my msdn subscription because ot was linked to the email i gave.
So they assumed it was a DS key. which is a total load a rubbish.. 
anyway i tried another key and it work flawlessly i didnt have to edit install.wim or add a PID file to sources.
later i retried my key back on the old hp it was installed on and guess what it worked.. so even though i deactivated and uninstalled win 8 off my old pc, the key still wouldnt work on a new pc.. 
overall i wasted a spare win8.1 pro key i owned because MS cant get their act together, and i also wasted 3days.
i want to try calling MS first of all to complain about their useless support & secondly to see if they can remove the hp activation off my key so that it can be reused.. my hp cant last 3hrs without crashing.. i spilt coffee all over it lol and was too
lazy to pull it apart, so i left it to dry and went bought a new pc..
it was a dualcore that was struggling with todays apps and OS..
thanks for the help :)
Huss