The type attribute cannot be present with either simpleType or complexType

Okay, I was struggling with this one for a while and couldn't find any answers on the net and it's one of those things that turn out making you feel stupid.

My xsd schema wouldn't validate. It failed with the error message mentioned on the title of this post: "The type attribute cannot be present with either simpleType or complexType." The relevant part of my schema was:

<xs:complexType name="ct_tuning">
<xs:attribute name="style" type="xs:string" use="required" />
<xs:attribute name="key" type="xs:string" use="required">
<xs:simpleType>
<xs:restriction base="xs:string">
<xs:pattern value="[a-gA-G]" />
</xs:restriction>
</xs:simpleType>
</xs:attribute>
</xs:complexType>

Now what could possibly be wrong with this that???

Well, it turns out the error message is not helpful at all and doesn't make any sense.

The problem with this snippet is that the attribute has already been given a type.If you notice the declaration in bold you'll notice that the attribute named "key" has been declared with type="xs:string". By declaring the simpleType underneath I am declaring its type twice.

Deleting the type="xs:string" from the declaration solved the problem.