HELP: Blank Spaces at the End of PHP files in WP-Admin

Hey there friends.

After a long series of customizations, I finally decided that I could switch my site over from it’s original domain/wordpress to the domain its self. After following the codex instructions, backing up my files, and so on, I did the switch and the site looks fine, but is without two important plugins. Because of this, I tried to go to mydomain/wp-admin, and I got

Warning: Cannot modify header information – headers already sent by (output started at /home/content/t/e/a/teamwin/html/wp-admin/includes/import.php:175) in /home/content/t/e/a/teamwin/html/wp-includes/pluggable.php on line 1699

I did some searching around and realized that there were 2 blank spaces added to the bottom of /home/content/t/e/a/teamwin/html/wp-admin/includes/import, so it wasn’t working. I took out these blank spaces, and another, similar warning came up, just with another file mentioned in place of the file i adjusted.

I did the same to this file and yet another came up. I now have taken two blank spaces out of the bottom of at least 20 php files.

Does anyone know why this happened or how I can fix it more quickly? As of right now, I still can’t access my-admin, which doesn’t exactly work well for maintaining a site.

Solutions?

cheers,