• You already did most of the basic troubleshooting; hardware acceleration, clearing cache, renaming the Normal template, and reinstalling ArcMap.
  • Check whether ArcGIS Online has been added as a portal in ArcMap
  • We have discussed the environment of the user machine and project: 
    • User works through VPN, but the issue just happens recently, when she has been using VPN long before.
    • The layers in the project are most likely to have the same coordinate projection.
  • Suggest opening a new blank and adding a base map to test the connectivity. 
    • ArcMap > My Templates > Blank Maps > Add Data Dropdwom > Add Basemap > Select Basemap and Add to the map.
  • Notice that the base map was too slow when tried to zoom in/out.
  •  Add a direct connection of map services in ArcMap in a new blank map. 
  • Catalog > Double-click the services > Drag the desired base map into the map.
  • Zoom in/out and pan the base map and notice that no freezing happens, and it works faster compared to the previous base map.
  • Test it from the existing project to evaluate the performance, and the ArcMap performance was better. No freezing occurred when zooming in/out or panning the base map.

You have two inquiries: 

  • Why does adding a direct connection to the base map increase the performance? 
    • Using a base map from Add Data will download a package that references the service URL. Therefore, they take longer to initialize, render, pan and zoom.
    • Whereas when you add the base map from ArcCatalog, the base map is accessed directly from the service URL. It makes this workflow more efficient and performs better.
  • What is the optimum/ideal internet speed? 
    • There is no ideal internet speed for this matter, however, there are few documentation/articles that discussed on the factors related to this issue. 
      • Connection interception from ArcGIS Online - can occur if a Server connection is broken or has a very slow connection.
      • Using VPN with a big amount of data added - refer to this discussion (Working remotely over VPN )

There are several workarounds for this issue in the documents below that you can still try. 

As agreed, I will proceed by marking this case as closed. However, should you require any additional assistance from my end, you may reach us either by replying to this email or by calling 888-377-4575 (providing the case number), and we will be more than glad to assist you further. Our standard support hours are from 5.00 A.M. to 5.00 P.M. (Pacific Time), Monday through Friday
 
To add any additional information or for the detailed status of this case, please visit the My Support portal available on the support website at http://support.esri.com.
 
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