I'm trying to make a unattended windows xp cd and i'm at at the step where I am suppossed to rename the unattended.txt file to winnt.sif , but it still remains as a .txt file and doesn't change the format to .sif? is this right? or should it change the file format?

you need to manually change the file extension, go to my computer. then click

tools -> folder options -> tab "view"

I suggest choosing/unchecking the following

-Show Hidden Files & Folders

-Hide Extensions for known file types

-Hide protected operating system files.

In any open explorer window, go to Tools > Folder options > View Tab, uncheck Hide extensions for known file types. This will enable you to change the file extension while renaming files.

Alternatively, when you save the file from notepad or other editor, wrap the file name in quotes in the Save As dialogue. --> "winnt.sif"