The installer copies files to the server hosting the SQL Server instance using the hostname\c$ hidden share.

If the user that is specified for setup.exe does not have enough permissions to install Apex, then the Apex components will fail and the following error is generated:

An exception occurred: Not enough permissions to enum server shares.

In addition, the security policy on the machine that is hosting the SQL Server instance may have the Network access: Sharing and security model for local accounts policy set to Guest only, which would cause the remote connection to login as a guest and not a user. This can be changed to Classic if required.