Hi I have recently installed PHP on to a 64bit computer with a Vista Business OS. I am trying to run a php page on the local IIS7 server which came with the OS. I get a 500 error when I launch the page which gives no clue as to what is causing the fatal error. I have loaded the MS tool 'PHP Manager for IIS' to ensure that my PHP is properly configured, this also writes a log of errors running IIS, this log tells me that there was a problem loading the dynamic library file 'C:\Program Files (x86)\PHP\ext\php_mssql.dll' which could not be found!
This is where I need some help! When I downloaded the PHP files I placed them in a directory called 'PHP' with a copy of php.ini moved to the windows directory and php5ts.dll & libmysql.dll moved to C:\WINDOWS\system32 directory. The php.ini file was edited by removal of the semicolon to activate the extension directory and session.save_path. (the extensions php_mysql.dll & php_mysqli.dll were initially activated however since the exercise I am following does not connect to a DB I have restored the semicolon to edit them out) The IIS error log has drawn my attention to the files in 'C:\Program Files (x86)\PHP\' which have been added by a process which I was not aware of and in particular in the \ext directory I note that the file 'php' which is a configuration file, is a rearrangement of the php.ini file which I copied to the WINDOWS directory. Also that all of the extension files have been activated in this version unlike the original copy (They are in a different location in the 'php' file, at the end).
I have tried editing these extensions out to see if the webpage would run but without success! The missing file reported in the IIS error log can be seen in the directory listed and incase I was going doolally I copied the file name from the report and pasted it into the search box in the directory in question, and sure enough it was found! Any suggestions on what is going on here?
Can anyone help me find where I have gone wrong with the configuration of PHP or IIS, or is this a security issue?

Hi for the benifit of the 189 viewers of this thread and other Wrox p2p users I have bottomed the problem discussed above as follows:
My 64bit computer has been a step too far for a lot of developer software and it has taken the best part of two years for PHP and associated software to catch up. Let me explain: I have been trying to learn how to program in OOP using PHP, my version 5.2.6 failed to work satisfactorly with classes and their functions. I loaded version 5.3.3 but its instal file makes no mention of a 64bit configuration method so I downgraded to version 5.2.14 which was the version I was using when I wrote my first post on this thread. A member of MS web team suggested that I download their IIS Manager which I did and now I have worked out that the files written to the directory 'C:\Program Files (x86)\PHP\' were put their by the IIS Manager.
The real conflict with the operation of this version of PHP comes from conflicting version data in PHP's files, some where old files from version 5.2.10 carried over and the consequence is that part of the configuration setup becomes invalid producing the 500 error.
In the interim while I was struggling trying to workout what was going on I tried replacing IIS with Apachi, but I couldn't find a version other than for 32bit platforms, the best advice given was 'RTFM' (which incidently says nothing about a 64bit project even being on the cards).
I have now reverted to PHP version 5.3.6 with IIS and have let the IIS manager work out the configuration which has successfully completed, my next issue is that some of the OOP class functions in PHP V 5.3.6 are being reported as not safe to rely on the system's timezone settings, so much for backward compatability!
Hope this helps someone out there.