WinXP: Unable to Import Registry Script!

I've always got my way around in Windows and feel quite comfortable with the registry. But this one flicked me off..!

Ok - The situation was that my XP user-id was changed, say xxxx to yyyy. Now the problem came when my associated applications wouldn't start due to "Path" entries to "My Documents" directory. I figured out the problem in a matter of seconds, hence exported the whole branch for that application into a file, say app.reg. Now, I simply replaced all of the 'xxx' to 'yyyy'. All I had to do was to Import (rather "Merge") as you see on the file options.

Here comes the problem - Whatever I did, I wasn't able to import. Finally, I painstakingly changed all these 78 entries "manually" (whoof! long time that I did any redundant tasks!).
Error: C:\app.reg : The specified file is not a registry script. You can
import only registry files or binary files.

Just after I did this one, I read a small bit of an article which said "Save the file in ANSI/ASCII format and not the UNICODE format that the registry (may) actually exports the file as." So that was it! It then imported smooth and fine!