Re:unable to create database user on mysql/linux
Have tried to replicate this issue locally but couldn't, make sure the user you are trying to create not already existed in the Database server.
73100420 :- <Error Error-Code="73100420">Database user could not be added.</Error>
Some common error with code plus description located in C:\Program Files\Advanced Communications\HostingController\INI.
You can also enable logging for database creation issue in HCadmin :: My Server :: Debug setting. After that error time when you will encounter error on db , a log file will generate in db server path C:\Program Files\Advanced Communications\HostingController\log