Validating XML Schema Documents
By default, XML Schema files are validated as you type. To change this, open the Preferences dialog box , go to , and deselect the Enable automatic validation option.
To validate an XML Schema document manually, select the 
Validate action from the
Validation toolbar drop-down menu or the menu. When
Oxygen XML Developer validates an XML Schema file, it expands all the included modules so
the entire schema hierarchy is validated. The validation problems are highlighted directly in
the editor, making it easy to locate and fix any issues.
Validation of an XML Schema containing a type definition with a
minOccurs or
maxOccurs attribute having a value larger than 256 limits the value to 256
and issues a warning about this restriction in the Message panel at the bottom of the Oxygen XML Developer window. Otherwise, for large values of the minOccurs and
maxOccurs attributes, the validator fails with an OutOfMemory error
that might make Oxygen XML Developer unusable without restarting the entire
application.Important: If the schema imports only a namespace without specifying
the schema location and a catalog is set up to
map the namespace to a certain location, both validation and the schema components will
correctly identify the imported schema.