Quote - i don´t have enough disk space on hard drive

I have a similar problem, only it's money that I'm short of!

As a temporary measure, see if you can move some data files to to CD/DVD, that may give you enough free space to defragment, which may give you a little more space in you have not dedefragment fro a while. Also empty the Recycle bin, clear your browser cache, cookies, and Windows Temp folder.  See if you can compress some files. Specific to Poser, set your 'Max cached renders' to a low number like 2. Also set a low 'Max undo level'.