Description:
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The PHP MSI while configuring IIS FastCGI on 64 bit machine uses \\localhost\Admin$ to overcome SYSWOW64 redirection. I have found machine where \\localhost\Admin$ is not reachable. This fails running of fcgiext.js script which means the FastCGI script mapping is missing on those machine. This leads to a bad user experience.

Another thing to note that this is happening with PHP5.3.1 MSI too. So this should be fixed at both the place.

Reproduce code:
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There is no code to reproduce this error as the bug is in Windows MSI.

Expected result:
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MSI while selected to configure IIS FastCGI should do the script mapping and add index.php to default document list.

Actual result:
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Script mapping as well as index.php in default document missing.