Attempting to automatically create or update metadata or clicking the Create/Update Metadata button yields the warning message Unable to create/update metadata.
This error usually appears because the location where ArcCatalog is attempting to create or update metadata is read-only. For example, the data may reside on a CD-ROM, or in a shared folder on the network or a geodatabase for which you have read-only permission.
For raster datasets this error may appear because the dataset uses LZW compression, and you currently do not have a license to use this type of compression. For more information, search for “LZW license” in the ArcMap on-line help.
Copy the item to a new location, then create metadata for it. Or, if appropriate, obtain an LZW license.