Documentum D2-config. Getting error "Failed to initialize class cache" upon sign in.

You may find more details in the application server log. Sounds like maybe the account you are running you app server as may not have access it needs to the dfc.data.dir location it needs. When dfc initializes it will create a cache directory if it does not exist, then connect to the global registry to find out what modules it should load into cache.

More details would help to tailor a potential fix suggestion. Can you provide the application server details, where the app server is installed to, what account you run it as and any corresponding stack/error in the application server logs.

Generally you will find the cache under {appserver}/bin in a folder named "documentum". You can also check your dfc.properties file to make sure there is no override to set the dfc.data.dir. For more detailed information you should be able to refer to dfcfull.properties which contains all the parameters for dfc.properties with explanations of defaults and sample values.

The above should exist in your repository.

/System/Modules/D2/D2BofServices

Which is a dmc_module object type. Sounds like the D2 Dar installation(s) may have failed during running the D2 installer? You may have to install the DAR files manually.