Description:
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We have been using Apache with PHP. And this new project required developing on IIS+PHP.

Issue, is the installing TS version of PHP removes non-TS installation of PHP affecting existing configured servers.

I had Apache running with 5.2 and then when setting up IIS7 to run PHP the installer removed the files required by Apache server. 



Reproduce code:
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<no code>

Expected result:
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The installer should not tamper the existing installation. Even when choosing to install the non-TS version of PHP, the installer removed the files installed by the previous TS version installer.

I have discussed this here as well: http://forums.iis.net/t/1161449.aspx

Currently I have IIS and Apache server both running on my Win 2008 x64 version. 

Actual result:
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Running thread-safe PHP MSI installer removes non-TS installation of PHP and vice-versa.