When a WMS service is added to ArcMap, none of the WMS layers draw. The WMS layers are listed in the Table of Contents, however all the checkboxes are greyed out, signifying that the layers are on" but not visible.
** The feature addressed in this article is only available in ArcGIS 9.0 Service Pack 2, which can be downloaded through the link in Related Information, below. **
A number of things may cause WMS layers not to draw:
- The WMS service is version 1.0.0. and you are using ArcGIS version 9.0.
- The data frame is in a coordinate system not supported by the WMS service. Pre 9.2 versions of ArcMap will only draw WMS layers in a coordinate system that is supported by the WMS server.
Note: At version 9.2 ArcMap will draw WMS layers in all ArcGIS supported coordinate systems, even if the WMS server does not support the given coordinate system.
- The spatial envelope of the data frame is outside of the LatLonBoundingBox specified by the WMS service capabilities file. For example, the request contains an X value that is greater than the maximum X specified by the service. Depending on the server, an error may be reported, or it is possible that a blank image will be sent.
- The WMS service may not be compliant with OGC specifications. For example, the server may be specifying the LatLonBoundingBox in incorrect units, such as meters or feet. The LatLonBoundingBox should be specified in decimal degrees.
- The size of the image requested by ArcMap is beyond the size limits allowed by the WMS server. This is likely to occur if you are attempting to draw WMS layers within a large size layout. In such cases, the WMS server should report an error.
Solution or Workaround
The causes given above have corresponding numbered Solutions below:
This issue has been resolve in ArcGIS 9.1. <a href='http://support.esri.com/en/knowledgebase/techarticles/detail/27937' target='_blank'>Bug:WMS layers do not draw if the WMS service version is 1.0.0</a>
A WMS service may only support a limited set of coordinate systems. If you are using a pre 9.2 version of ArcGIS you can use set a new coordinate system for the data frame to one that is supported by the WMS service layer(s). <a href='http://support.esri.com/en/knowledgebase/techarticles/detail/27949' target='_blank'>How To: Set a new data frame coordinate system (spatial reference) to one that is supported by the WMS service(s)</a>
Zoom in to a spatial extent that is within the bounding box specified for the layer. The bounding box for each WMS layer is listed in the WMS service capabilities file. <a href='http://support.esri.com/en/knowledgebase/techarticles/detail/27948' target='_blank'>How To: View the WMS service capabilities</a>
There is no workaround. Check the WMS service capabilites file to determine if the units are correct. <a href='http://support.esri.com/en/knowledgebase/techarticles/detail/27948' target='_blank'>How To: View the WMS service capabilities</a>
Reduce the page size of the layout or reduce the size of the data frame on the page layout that contains the WMS layers until an an image size acceptable to the WMS server is requested. Different WMS servers may support different image size requests. Currently, there is no way for ArcMap to report acceptable sizes.