I have temporarily removed my old 1TB hard drive which has Windows 7 on it. I have upgraded the system to a new 256GB SSD drive and have done a fresh install of the same OS (from the same DVD in fact, so the licence key is the same of course).
I want to use the old 1TB disk as a secondary drive in the PC and use the SSD as a boot drive (the new C:\ drive). I don't want to format the old drive because there's a large amount of data in the old C:\ partition that I want to keep (hundreds of GBs, but none of it is critical).
Is the presence of the old OS on the old drive likely to cause any problems if I add the old disk back to the system as a secondary drive? Do I need to take any steps to somehow disable / delete / disarm the old windows installation on the old drive? I'm worried that having two identically keyed installs on the same system might invalidate the license or something like that (I don't know much about how Windows licence detection works to be honest).