Unable to write the following file:

[fatherdead]

C:\Program Files (x86)\Zygor Guides Client\data\models\wow_products-980388928.model

Any ideas, client will not update to latest version?

[ZG Support 1]

Try going to your Program Files (x86) folder and delete the Zygor Guides Client folder in there, then download the installer from the Members Area again for a fresh client install.