Windows Live Writer has been upgraded and I wrote a post on the Metaweblog standard conformance of WLW in a previously.

The metaWeblog.getCategories I suggested to use to get it to work with Windows Live Writer will now fail since Writer expects that a description is passed in the response.

That is your response has to look like this, watch the lines 18-21 and 32-35.

 1 <?xml version="1.0"?> 2 <methodResponse> 3 <params> 4 <param> 5 <value> 6 <array> 7 <data> 8 <value> 9 <struct>10 <member>11 <name>categoryid<name>12 <value>1</value>13 <member>14 <member>15 <name>title< span="">name>16 <value>Category 1< span="">value>17 <member>18 <member>19 <name>description< span="">name>20 <value>Description 1< span="">value>21 <member>22 </struct>23 <struct>24 <member>25 <name>categoryid< span="">name>26 <value>2</value>27 <member>28 <member>29 <name>title< span="">name>30 <value>Category 2< span="">value>31 <member>32 <member>33 <name>description< span="">name>34 <value>Description 2</value>35 </member>36 </struct>37 </value>38 </data>39 </array>40 </value>41 </param>42 </params>43 </methodResponse>