Rider ignores Use64BitIISExpress


I am currently evaluating Rider and found a small issue. We have a ASP.net application with some 64bit dependencies. To ensure the application works during development, we have enabled the 64bit IISExpress via the Use64BitIISExpress option in the csproj. Unfortunately Rider ignores this setting and launches the 32bit IISExpress which leads to a BadImageFormatException.

Is this a known bug that will be fixed? Is there another setting that tells Rider to use the 64bit version of IISExpress? I couldn't find anything in YouTrack and also the latest Rider 2018.3 EAP6 suffers from this issue. 


Kind Regards


1 comment

Hi Daniel,

No, it is not known. I've created an issue in Rider tracker: https://youtrack.jetbrains.com/issue/RIDER-22441. Thanks for drawing our attention to it.


Set the path to x64 IIS Express executable and change the working directory accordingly in your run configuration:


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