GD configuration problem

I'm having trouble getting PHP to admit that the GD package exists. Or several other packages that I would expect to see. Some months ago I wrote a PHP script that does some simple processing on images. GD had the functionsI needed, so I used it. I got it working and used it a few times. Then I wanted to add some more functionality which was available in the ImageMagick package. So I rewrote it (saving the original) using ImageMagick. But my PHP turned out not to support ImageMagick. So I downloaded a newer PHP, and turned on ImageMagick in the config file. But it didn't work -- my PHP didn't include ImageMagick. After a few frustrating tries to get ImageMagick working, I went back to the old version of the script. But now the GD version doesn't work (error messages below). I now have three different PHPs on my computer: * The one that was included with my Cygwin installation * The one that was included in my XAMPP distribution * One that I downloaded directly from the PHP site. I get the same errors on all 3. Okay, that's the lead-in. Here are the error messages: PHP Warning: PHP Startup: Unable to load dynamic library 'bz2' (tried: C:\xampp\php\ext\bz2 (The specified module could not be found.), C:\xampp\php\ext\php_bz2.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'curl' (tried: C:\xampp\php\ext\curl (The specified module could not be found.), C:\xampp\php\ext\php_curl.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'fileinfo' (tried: C:\xampp\php\ext\fileinfo (The specified module could not be found.), C:\xampp\php\ext\php_fileinfo.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'gd2' (tried: C:\xampp\php\ext\gd2 (The specified module could not be found.), C:\xampp\php\ext\php_gd2.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'gettext' (tried: C:\xampp\php\ext\gettext (The specified module could not be found.), C:\xampp\php\ext\php_gettext.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'mbstring' (tried: C:\xampp\php\ext\mbstring (The specified module could not be found.), C:\xampp\php\ext\php_mbstring.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'exif' (tried: C:\xampp\php\ext\exif (The specified module could not be found.), C:\xampp\php\ext\php_exif.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'mysqli' (tried: C:\xampp\php\ext\mysqli (The specified module could not be found.), C:\xampp\php\ext\php_mysqli.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'pdo_mysql' (tried: C:\xampp\php\ext\pdo_mysql (The specified module could not be found.), C:\xampp\php\ext\php_pdo_mysql.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'pdo_sqlite' (tried: C:\xampp\php\ext\pdo_sqlite (The specified module could not be found.), C:\xampp\php\ext\php_pdo_sqlite.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'php_openssl.dll' (tried: C:\xampp\php\ext\php_openssl.dll (The specified module could not be found.), C:\xampp\php\ext\php_php_openssl.dll.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: PHP Startup: Unable to load dynamic library 'php_ftp.dll' (tried: C:\xampp\php\ext\php_ftp.dll (The specified module could not be found.), C:\xampp\php\ext\php_php_ftp.dll.dll (The specified module could not be found.)) in Unknown on line 0 PHP Warning: Cannot open 'C:\xampp\php\extras\browscap.ini' for reading in Unknown on line 0 PHP Fatal error: Unable to start standard module in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'bz2' (tried: C:\xampp\php\ext\bz2 (The specified module could not be found.), C:\xampp\php\ext\php_bz2.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'curl' (tried: C:\xampp\php\ext\curl (The specified module could not be found.), C:\xampp\php\ext\php_curl.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'fileinfo' (tried: C:\xampp\php\ext\fileinfo (The specified module could not be found.), C:\xampp\php\ext\php_fileinfo.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'gd2' (tried: C:\xampp\php\ext\gd2 (The specified module could not be found.), C:\xampp\php\ext\php_gd2.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'gettext' (tried: C:\xampp\php\ext\gettext (The specified module could not be found.), C:\xampp\php\ext\php_gettext.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'mbstring' (tried: C:\xampp\php\ext\mbstring (The specified module could not be found.), C:\xampp\php\ext\php_mbstring.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'exif' (tried: C:\xampp\php\ext\exif (The specified module could not be found.), C:\xampp\php\ext\php_exif.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'mysqli' (tried: C:\xampp\php\ext\mysqli (The specified module could not be found.), C:\xampp\php\ext\php_mysqli.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'pdo_mysql' (tried: C:\xampp\php\ext\pdo_mysql (The specified module could not be found.), C:\xampp\php\ext\php_pdo_mysql.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'pdo_sqlite' (tried: C:\xampp\php\ext\pdo_sqlite (The specified module could not be found.), C:\xampp\php\ext\php_pdo_sqlite.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'php_openssl.dll' (tried: C:\xampp\php\ext\php_openssl.dll (The specified module could not be found.), C:\xampp\php\ext\php_php_openssl.dll.dll (The specified module could not be found.)) in Unknown on line 0 Warning: PHP Startup: Unable to load dynamic library 'php_ftp.dll' (tried: C:\xampp\php\ext\php_ftp.dll (The specified module could not be found.), C:\xampp\php\ext\php_php_ftp.dll.dll (The specified module could not be found.)) in Unknown on line 0 Warning: Cannot open 'C:\xampp\php\extras\browscap.ini' for reading in Unknown on line 0 Fatal error: Unable to start standard module in Unknown on line 0