VSTA hosts use a host specific folder under %My Documents% (or %Documents for Vista) for various purposes. This is where the settings file is stored and is the default save location is for new VSTA projects for the host (unless a different location is specified under the registry entry NewProjectLocation).
Most configuration settings can be updated by deleting the host context hive under the local machine hive (see Note 1 registry location), then running vsta setup for the host. Unlike other registry settings, to update which folder is used in %My Documents% the host context hive under the local user hive (see Note 2 for registry location) must be deleted prior to running vsta setup for the host, and will be populated the next time VSTA is run for the host....