FDV here, too lazy to log in.
1. You didn\'t say if you are slipstreaming SP3 into an existing SP2 slipstream. If you are, don\'t. I don\'t want to type for 10 minutes about the reasons this is an ill-advised idea, just don\'t, trust me.
2. But say you aren\'t. You are most likely specifying a path and you should stop doing this. The UPDATE command will look for an I386 directory--this is hard-coded into the file.
So, if you were to create a slipstream by typing [drive]:SP3I386UPDATEUPDATE -s:[drive]:I386 like you used to see in some examples on various websites (before people actually tried it, found it didn\'t work, and fixed their sites), you\'d get an error, because UPDATE would be looking for your Windows 2000 files in [drive]:I386I386.
Note also that none of the drive letters may point to a CDRom or that would result in an error as well.
Best of luck
Fred