Registry and Registry Settings Changes in VSTA v 2

VSTA v 2 host configuration registry entries are similar to VSTA v 1’s- there are a few new entries and a change in how they are organized.

Two of the most noticeable differences are the “2.0” subkey and “VSTAVersion” entry.  VSTA v 2 entries are stored in the “2.0” subkey, which resides beneath the host subkey in the VSTAHostConfig hive.  The VSTAVersion entry with a value of “9.0” is a required entry; without it the vsta setup command will not work (see Note 1).  In the VSTAHost hive, VSTA v 2 entries are stored in the “9.0” subkey beneath the host subkey while VSTA v 1 entries are stored in the “8.0” subkey.  This setup allows a host to be registered both under VSTA v 1 and VSTA v 2.

Other new entries for the configuration hive include “UpgradeFrom” and “UpgradeHelper” which are used to migrate existing VSTA v 1 add-ins, “HelpNamespace” which is used to register custom help files, and “VSItemTemplatesLocation” which is similar to the “VSV#ProjectTemplateLocation” entries.

As in VSTA v 1, the VSTAHost hive must be deleted and regenerated with vsta setup to reflect most changes in the VSTAHostConfig registry.  To avoid causing any problems with a host registered under both VSTA v 1 and VSTA v2, delete the VSTAHost\<HostID>\9.0 subkey instead of the host’s key prior to running setup.

In-Process Host Registry Entries
Unlike VSTA v 1, where In-Process Host (IPH) registry entries had to be added directly to the VSTAHost hive, VSTA v 2 stores these entries in the VSTAHostConfig hive.  To register an IPH, add the “VSTA” then “InProcHost” subkeys beneath the “2.0” subkey beneath the host’s key in the VSTAHostConfig hive.  Then delete the “9.0” key beneath the host’s key in the VSTAHost hive and run vsta setup.

Note 1:  The “VSTAVersion” entry requires the value “9.0”.  If this entry with this value is not found when vsta setup is run an error will occur.  The error message will state that one or more components cannot be found and the application needs to be re-installed.  To avoid this message, register the host using a value of “9.0” in the “VSTAVersion” registry entry.