Crashing MXDs, "ArcGIS online is not connected"

[StewartGalloway]

MXDs crash.  I am using ESRI Basemaps which take a long time to load.  After the basemap loads the other feature class layers sometimes do not display.  When I first open an MXD I get the notice "ArcGIS online is not connected" - is this the cause?

What is the cause of not being able to connect to ArcGIS Online?  Is it our IT security blocking it?  How do I determine if it is security? 

[Anonymous User]

The video below shows how you can check your connectivity to ArcGIS Online when ArcMap is open:

If you are connected to the internet but you aren't connected to ArcGIS Online it is likely one of the required domains is being blocked either by your IT security settings or an antivirus. Here is a document from our Trust ArcGIS | ArcGIS site about required domains:

http://downloads.esri.com/resources/enterprisegis/AGOL_Domain_Requirements.pdf 

[StewartGalloway]

Thanks Katie!  I am using the PDF to following up.

Can you please send a link to that video?  Thanks very much.

Stew

[AndreaB_]

Does anyone have an updated copy of the sites we should ask IT to put on a trust list? thanks