I'm in the process of deploying a couple of Edge Transport servers in a DMZ domain. The installation on each of them failed at the same point with the exact same error message:
Active Directory operation failed on localhost. This error is not retriable. Additional information: The parameter is incorrect.
Active directory response: 00000057: LdapErr: DSID-0C090D14, comment: Error in attribute conversion operation, data 0, v23f0
Unfortunately I was not able to find information about the LDAP error code, not even a mention on a website or forum. So I went a couple of steps back and checked my implementation plan. Installing the prerequisites for Edge Transport is fairly simple and the DNS suffix was already set because this server is a domain member. Couldn't think of a mistake I made.
A quick search on the internet pointed met to an article Jaap Wesselius wrote a time ago: Edge Transport server fails in Active Directory domain. The issue Jaap describes is very similar, although the actual LDAP error is slightly different and was present in CU5 and CU6. Unfortunately I can confirm this issue is still there in CU7, assuming both our issues have the same root cause.
Due to time constraints I was not able to involve PSS to investigate the issue further and had to choose for the workaround of installing Exchange while the servers is in Workgroup mode. After the Edge Transport role was installed I was able to add the server to the domain and Exchange was functioning properly.