Is there something that you're not telling us about your system?

If you're installing on an Intel iMac see this article:
http://www.windowsreference.com/gene...nstalling-sp3/

Otherwise, if your 80GB HDD has multiple partitions and the portion where the OS
is installed is crowded, see these articles:

The hard disk space requirements for Windows XP Service Pack 3
http://support.microsoft.com/kb/947311

Error message when you try to install Windows XP Service Pack 3: "You do not
have enough free disk space on %SystemDrive% to install Service Pack 3"
http://support.microsoft.com/kb/949385

If none of the above apply: Microsoft provides free setup and compatibility
support for customers who install Windows XP SP3. The details of this procedure
are contained in the release notes article.

Release notes for Windows XP Service Pack 3
http://support.microsoft.com/kb/936929

Good luck!

"GregM" wrote in message
...
When installing SP3 I get an error that states "Not Enough Disk Space" Which
I am hoping is wrong as I have 40GB of free disk space. Has any one run into
this issue?

I am running XP Pro an a dual core system with 3gb of ram and 80GB HD

Any ideas?