A WMS layer contains different subayers. While some of the WMS sublayers are drawing, others from the same WMS service are not drawing.
** 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. **
There are a number of possible reasons:
1. When adding a WMS layer to ArcMap, only the first 20 sublayers are automatically turned on. The remaining sublayers are off by default.
2. You can use the Layers tab in the WMS Layer Properties dialog to configure a subset of WMS sublayers to display in the map. It is possible that the sublayer(s) are not included in this subset.
3. The data frame is in a coordinate system not supported by the sublayer(s) within the WMS service. The sublayer(s) will not draw in an unsupported coordinate system. This is an issue for pre 9.2 versions of ArcGIS.
4. The WMS sublayer may be scale dependent. That is, the sublayer will only draw within a certain scale range and the map is currently outside this range.
Solution or Workaround
The causes listed above have corresponding numbered solutions given below:
- Locate the specific sublayer(s) in the Table Of Contents and click their checkbox to make them visible. You may also do this within the Layers tab of the WMS Layer Properties dialog.
- Choose the WMS sublayers you want included in the map from the left panel and move them to the right panel using the selection buttons in the center of the dialog.
- 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.
If you are using a pre 9.2 version of ArcGIS you can use the Change Coordinate System dialog to change the data frame's coordinate system to one that is supported by the sublayer(s) of the WMS service.
<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 to a map scale within the visibility range of the sublayer. WMS services may include a <ScaleHint> tag which is then reported by ArcMap as the minimum and maximum scale for the sublayer. These values should indicate at which scale the sublayer should draw.
This tag is not a requirement. There may be cases where WMS layers are scale dependent, but do not not have a <ScaleHint> tag. In such cases the layer will draw within a certain scale range, but ArcMap is unable to report the scale range in the Layer Properties dialog. This is a known limitation.