https://help.sonatype.com/display/NXRM3/User+Interface+Overview references to the System Status Check icon are not present.
I was mulling updating screens but this seems to be just adding an unknown element to them.
Please also consider adding details or a distinct page about tips to help solve these issues when they arise. There are a lot of items there and it is unhelpful to assume that people will just know how to solve them without guidance. If you desire a distinct ticket for that let me know.