Q: I could not download data from the SRTM Global 90m server under Terrain Data in the Download Online Maps dialog. I get an error that the server does not provide image data. What does this mean and how do I download data from this server?
A: The SRTM Global 90m server is a WCS server and only provides grid information (DEMs). Like the error says, it does not provide imagery. Since you were downloading a base map from a server, the error was generated because you cannot use a grid file to create a base map.
If you want to create a base map, select one of the other servers that provide image or vector data (WMS, OSM, or WFS types) in the Download Online Maps dialog.
If you did intend to download a grid file instead, then do not select to download a base from the server. Instead, anytime the Open Grid dialog opens (e.g. when creating a new grid-based map type, adding a grid-based layer type, performing a grid calculation, etc), click the Download button to open the Download Online Grids dialog. Alternatively, click Grids | New Grid | Grid from Server to open the Download Online Grids dialog. From here, select the SRTM Global 90m server and layer under Terrain Data to download a grid file.
Updated November 12, 2018