Heat.exe will use the literal folder name when generating WIX xml for a directory structure. In special cases this can lead to built-in MSI property names being used in the Id attribute:
<directory id="user-content-AdminUser" name="AdminUser"></directory>
This causes the MSI costing process to fail and the MSI will lock up and eventually fail.
The solution would appear to be to maintain a list of built-in property names and never to use any of these values for directory Id's (or any other Id's for that matter).
Archive with sample heat output and also a sample WXS and MSI displaying the costing problem.
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