XAMPP Windows 1.8.0: I thought i better leave a quick note here. I am using Windows 7 Home Premium 64bit.
I installed xampp and it wont start apache. first for skype, which i resolved. But ...
Apache will not start because all the httpd conf files; including extras - for some reason have "C:C:" in the path. I had to replace them all to start xampp/apache.
Sample errors (if you run httpd from command prompt):
httpd: Syntax error on line 35 of C:/xampp/apache/conf/httpd.conf: ServerRoot must be a valid directory
httpd: Syntax error on line 456 of C:/xampp/apache/conf/httpd.conf: Syntax error on line 17 of C:/xampp/apache/conf/extra/httpd-xampp.conf: Invalid LoadFile path C:C:/xampp/php/php5ts.dll
AH00526: Syntax error on line 28 of C:/xampp/apache/conf/extra/httpd-multilang-errordoc.conf:
<Directory "C:C:/xampp/apache/error"> path is invalid.
After this i edited every file in C:\xampp\apache\conf\extra
Hope it helps someone like me