We, as a development team for a script provider, assume that you're on a fully functioning webserver which allows PHP to write to files on the server; configuration of your web server is out of the scope of the support provided here.

For IIS you'll need to ensure that IUSR, DefaultAppPool and IIS AppPool\<<AppPoolName>> have full write permissions (followed by an iisreset); other than that, none of us utilize IIS as a web server so we'll be little help in the configuration and troubleshooting of IIS.

The UBB.threads System Requirements Test is updated more often than UBB.threads, it is also privately developed by me and is not a part of the UBB.threads packages by design. The official download link is Download the UBB.threads System Requirements Test. This test script however does no additional checks for IIS, in fact it does less checks as a predictable location of ImageMagick cannot be done. Additionally, it does not perform any write checks to the file system.

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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