[musicman691]

First off there is no such thing a Kontakt 8; perhaps you meant Komplete 8.

There is no need to install both Komplete 8 and Komplete 10. About the only reason I could see is if you needed Battery 3 as well as Battery 4 (in that case I'd just install Battery 3 and it's content from the Komplete 8 installer). Your computer is probably getting confused having both sets of programs on it. I'd uninstall Komplete 8 and just install Komplete 10 and let the installer put the programs where it wants to; make sure to carefully select where you want to install the sample content to - that's a separate step in the installer.

And when you're done installing don't forget to activate them through NI Service Center as well as install any updates the Service Center finds. That drive you got from NI does not have the latest revisions of NI programs.

Just thought of something - you may have sessions that used the older RTAS version of NI plugins but the nice thing with PT10 is it can use both RTAS and aax32 format plugins. I know the latest versions of most NI programs lose RTAS capability but like I said - you don't need it in PT10. Also sometimes systems can have issues with having both the RTAS and aax versions of the same plugin.