This error has too many options to fix, one of them is below resolution -
In our case we were using a dynamic query which will send some results over the email with help of dynamic execution. when the query was executed using sp_send_mail it used to fail.
Failed to initialize sqlcmd library with error number -2147467259.
After couple of hours identified that query results using linked server was causing the issue.
An error occurred during Service Master Key decryption There is no remote user ' ' mapped to local user '(null)' from the remote server ' '. (Microsoft SQL Server, Error: 33094)
To fix this we need to run
ALTER SERVICE MASTER KEY FORCE REGENERATE
Once the above command executed linked server started working properly. The dynamic query started to work smoothly, which inturn resolved the issue.