aspnet_merge(0,0): Error occurred: An error occurred when merging assemblies: Unresolved assembly reference not allowed: [Custom.Assembly]

Question

I'm a long time Stack Overflow lurker, and this is my first question so please go easy on me.

I develop custom eCommerce ASP.NET Web Forms applications, and during publishing we merge all outputs to a single assembly.

I've been scouring the web trying to resolve the below error during publishing:

aspnet_merge(0,0): Error occurred: An error occurred when merging assemblies: Unresolved assembly reference not allowed:[OurCustom.Assembly]

This has never been an issue with any of our other projects, and I'm totally stumped.

I have tried:

• Checking out a clean project from our repo
• Removing than re-referencing all .dll's in the bin folder
• Using different versions of aspnet_merge
• Switching target framework (.NET 4.5, 4.5.1, 4.5.2)
• Turning computer off, then on again
• Sleeping on it

The .dll in question is used in all of our other projects, and has not caused this issue before.

Thanks in advance.

Answer 1

After much trial and error I was able to determine that our custom .dll the project was referencing was corrupted, even though it worked locally and in production. I copied in another version of the .dll that worked with in the other projects and was able to publish to a merged assembly.