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I have not used ArcMap for 2 months and suddenly it behaves strange: When starting a new map from scratch, I cannot add a basemap and I cannot create new (basemap or group) layers. I see the option and can click it and there is not even an error message, its just: nothing happens.
Even when adding a basemap, I see the selection window and can select, for example, OSM. But nothing happens after that, the program doesn't even crash...
I am using ArcMap 10.0
thanks in advance, I could not find anything like this using search.