Strongly Named Assembly Validation Works Locally But Fails On A Test Device

Question

In my applicaiton I am referencing a .dll which works fine locally. After I build the application for release and test it on another computer, the library fails to load. I have attached the processes to the Visual Studio Debugger on the test computer and the error messgae I get tells me that the strong name could not be veryfied.

To test on another computer, I simply build the solution for release and copy the entire Release folder to the other computer. All the .dlls, including the failing one, are there and all of the, except the one, are being loaded successfully. When I do the same thing but with the code that uses that .dll commented out, it all works just fine.

Are there any steps I am missing? It seems very odd that the library's strong name can be veryfied locally but on a test computer.

Answer 1

From your symptoms, it sounds like you might have Delay Signing on for that assembly? Take note of the section that reads:

With either the –Vr or –Vk option, you can optionally include an .snk file for test key signing.

Use the -Vr or –Vk option only during development. Adding an assembly to the skip verification list creates a security vulnerability. A malicious assembly could use the fully specified assembly name (assembly name, version, culture, and public key token) of the assembly added to the skip verification list to fake its identity. This would allow the malicious assembly to also skip verification.

You may have run that so it passes on your machine and not on deployment ones.

http://msdn.microsoft.com/en-us/library/t07a3dye(v=vs.110).aspx