Secondary windows install to new partition, now confused

Schenley

Honorable
Aug 16, 2012
12
0
10,510
So I'm much better with hardware then I am with software, and made a poor choice of installing a modded windows thinking I could use my regular windows activation key, when I found out I couldn't I then installed standard windows to a secondary partition and have bade that partition the bootable, after transferring everything over I needed or wanted to keep, I went into my disk management to delete the partition of the modded windows, but it's reading as the primary drive, and I receive a warning that it is currently in use. I'm currently in the process of making a backup just to be safe and everything, but is there something I'm missing to enable me to delete the previous partition without risking and serious damage?

specs are as follows:
Windows 7 Pro 64-bit (6.1 build 7600)
AMD FX -8350 Eight Core (resting at 4.0 GHz)
16g ram
Nvidia GeForce GTX 760 GPU
 
I've already installed my valid copy of windows onto another partition. I'm attempting to figure out if the pop up I get in disk management when I go to delete the old partition is just due to it being labeled a primary drive or if I need to do something else first.

it's like this. two partitions, C: and B:, modded windows installed on C:, but had issues, so installed my standard copy of windows onto B: and now use that as my bootable and everything, went to delete the C: partition to roll it into B: but received a pop up saying it's in use while I was using the Windows from B:
 
ah ok. I hear you now. I was really hoping to avoid doing that and was searching for another way. I'll probably end up going that route tomorrow if another option doesn't present itself.