I have Poser4 and 5 on my hard drive(C) and it's getting quite filled up. My other drive (D) has loads of room. Should I reinstall Poser4 and 5 on my D Drive or can I just drag all the files from C to D? TIA

I know you can MOVE P4 over, not sure about P5. Might try to COPY it over and see if it works from there.

Poser 4 depends on the runtime folder being located in the Poser folder. That leads me to believe that a re-install of Poser 4 would be necessary (someone with more indepth knowledge can correct me if I'm wrong here). However, I assume that you have loaded plenty of stuff in your Poser 4 runtime on drive C, so the wisest thing would be to re-install Poser 4 on the D drive, delete the new runtime on the D drive and drag the old runtime over from the C drive. That way you will have an identical Poser 4 installation on the new drive. Poser 5 can access multiple runtimes located anywhere. For Poser 5, you can drag the runtime folder to the D drive and access it from your original Poser 5 installation. The runtime is the folder that takes up the most disk space, so this would help you making space available on the C drive.

Of course, you can try to copy the entire Poser 4 folder to drive D as PabloS suggests, but since Poser also makes registry entries when installed and possibly affects stuff outside the Poser folder upon installation, it might create problems. Moving an entire installation of a software from one disk to another just by copy and paste is alwaays a bit risky.