Windows 10: 2 Off "C" drives

I have two SSDs both of which are mounted on separate "C" Drives.....W8.1 on one and W10 on the other.
To create extra space on W10 have decided to format the W8.1.
Have tried changing the drive letter in W8.1 so that I can open with W10 in order to format W8.1....drive letter change not possible, format greyed out.
Neither M$ Disk management or CCleaner could perform this task.
Any ideas would be appreciated.

:)

 

" SOFTWARE UPDATE FAILED "

SO HERE'S THE LINK TO THAT PIC

http://i26.tinypic.com/2ihbdco.jpg

CAN U PLZ CHECK IT ACTUALLY I HAVE USED THE NOKIA SOFTWARE UPDATER B4 ... BUT I DONT KNW WHY I M GETTING THIS ERROR NOW

 

" SOFTWARE UPDATE FAILED "

i have installed windows xp sp2

previously i was using windows media center i thought i might b facing this probs due to that but then i changed it to windows xp ! n moreover i have also shown to nokia service center executives but they were not having the latest updates available ......
my pc suite is showing that new update version of firmware is available but i cudnt download it

oh gawd wat to do ?

i tried in another pc then again i got an error u need to have minimum 256 ram

please cant it b rectified ? there must b any solution to this probs please help me guyz

god bless all of u thanx

 

It shouldn't matter, the win 10 OS when booting will assign drive letters to both, and the one that it boots from will be C:

Boot it up with your 10 and the extra ...

 

I can boot up separately with each but when I connect the two together it only recognises W10.

 

What does disc management show for the extra drive when booted into 10?

You should be able to reformat, allocate space, etc.

 

As stated already extra drive W8.1 does not appear when booting from W10.
I must emphasise I only wish to format W8.1.

 

Have you tried booting into safe mode with command prompt on the Windows 8.1 drive and run a format command?

 

You can also try: Download Active@ Partition Manager

 

Reasoning on my part suggests you cannot remove an O/S while it is operational.
Have finally solved the problem, or rather M$ solved it.
As already stated each SSD worked perfectly on their own.
After trying to get either to recognise the other.....at the third attempt Windows started to correct faults on W8.1 then started to correct faults on W10.....from there it was easy to change the disk letter on W8.1 to "E" then restart the computer with W10 to format W8.1.
My Thanks to all who replied.

 

Happy to hear you got it sorted out dencal *Smile