How to: Resolve error “The Module DLL C:WindowsSystem32inetsrvlogcust.dll failed to load. The data is the error.”

How to: Resolve error “The Module DLL C:WindowsSystem32inetsrvlogcust.dll failed to load.  The data is the error.”

This error might be caused for a number of reasons, but generally speaking the resolution is pretty simple. LogCust.Dll is a library used to log custom errors. There are a few IIS components like “Custom Logs” that depend on this Dll, but also there is “Tracing“. So, if you want to avoid this error message you need to make sure you have selected the right IIS component to be installed for the dependency to be satisfied. Generally speaking you can simply activate the entire Health and Diagnostics category.

The Module DLL C:WindowsSystem32inetsrvlogcust.dll failed to load.  The data is the error.

As mentioned the key/solution here is to install the Custom Logging feature. You can find this on the Add Roles section of IIS:

• Server Manager
  • IIS
    • Role Services: Add Role Services
      • Health and Diagnostics category: Custom logging/Tracing/The entire thing to be safe.

In my case I came across this error as I was playing with the shared IIS configuration and one of my servers did not have all the features the source server had. As you can imagine, what happens is that the new server receives the configuration which includes settings for features/roles it has not installed so the error is generated. Extrapolating this scenario you can observe this error in cases where a setting remains in IIS indicating it to use a particular feature/role that is not installed/active at that moment.