I'll try to be brief... I have installed Adobe CS5 Master Collection. But I could not install After Effects and Premiere Pro as they need 64 bit system. (I have 32 bit and cannot afford to buy another machine right now.) So I installed the CS4 version of After Effects and Premiere Pro from a page the software itself (Adobe Master Collection cs5) opened in the browser (after complete installation). Apparently, this special CS4 version of After Effects and Premiere Pro should accept the key for CS5 Master Collection. However, if I'm trying to use my CS5 key, it is not working!!!! I already tried re-installing Adobe CS5 Master Collection and currently have After Effects and Premiere Pro (the special CS4 version) as trial. Any ideas???