Posted By willem on 1/27/2025 8:30 AM

I did an upgrade to DNN 9.13.5 and I get this error: Error Could not load file or assembly 'System.Runtime.CompilerServices.Unsafe, Version=4.0.6.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. 

Any suggestions how to fix this?

Thanks!

Willem, I've several questions for you

1. What was the DNN version you had before running the upgrade?
2. Does your website have third party modules installed?
3. Did you follow the suggested DNN upgrade path (link)?

In order to avoid as many problems as possible while doing an upgrade make sure you review your third party modules before running the upgrade itself and double check the vendor offers you a compatible version for your third party modules; if they offer you a new version, update the module before running the DNN upgrade.

Regards,

Couple of things:

• Usually, the issue is that in the web . config there is a reference to a different version of a dll that in the bin folder actually resides. Solution: check the file in the bin folder, see what version it is and update the version in the web . config to that number. 
• As ActionForm was mentioned somewhere: there is no official support for 9.13.7 yet. Check in the Plant an App docs what the supported versions are. 
• If you have Plant an App modules and 2SXC installed in the same host, it is always a problem. It is 2 different idealogies that did not come together.