title: How to resolve Oracle RemoteOperationException: Error reading error from command
body: <p>I have recently been receiving the following error whenever I am asked to supply the host username and password in Oracle DataGuard's Enterprise Manager (EM) tool: RemoteOperationException: Error reading error from command. Any configuration or management that needs to be performed and requires the host credentials is throwing this error. This is one of the most unhelpful errors I have seen in a long time. I have checked all of the log files I can think of and I can't find any error logs or indications to the problem. I verified that I can log into the servers with the credentials that I was trying in EM, I verified the connection configuration through EM using the built in test tools, and I verified that all of the saved passwords in EM were correct. This was working on the initial installation. Sometime over the last couple of weeks it stopped working and I'm not sure why. The hosts are running Linux Red Hat 4 Enterprise and Oracle 10g.</p>