If you’re not planning on using isymphony, uninstall the module, then disable the service with:
chkconfig iSymphonyServerV3 off
Then restart asterisk and those errors should go away.
Settings -> Asterisk Manager Users over on the right is a user called cxpanel. You need to click on it, bring it up, change nothing, and click “submit changes” on the bottom. This will write the cxpanel user details in the proper config file.