I succeed in connecting to the following WMS in QGIS (2.14.15 LTR): https://secure.erlangen.de/arcgiser/services/Luftbild2016/MapServer/WMSServer?SERVICE=WMS&REQUEST=GetCapabilities
... with the following configuration:
The image is displayed, but in the Layer tree there is an error message
Returned legend image is flawed:
It is not flawed, because legend image url http://secure.erlangen.de/arcgiser/services/Luftbild2016/MapServer/WmsServer?request=GetLegendGraphic%26version=1.3.0%26format=image/png%26layer=0 seems to work:
Since error messages like this might be confusing to simple minded people, what might be wrong here? Do I miss any settings?
This seems only to occur in case of some configuration issues in our ArcGIS for Server / ArcGIS WebAdaptor environment and is not a general issue in QGIS not displaying WMS legends, as indicated by the screenshot below (WMS is http://sg.geodatenzentrum.de/wms_topplus_web_open)