IECUSTOMIZER
Hi Martin,
Usually as well as the COM registration under a HKCR key, you also add a key with a value of your toolbars CLSID to
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Toolbar\WebBrowser
or
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\Toolbar
But I cannot confirm that for Vista as I am using XP and Win2K. I kinda suspect that installing a toolbar without validating user access rights to the registry (ie using an installer), particuarly on a Vista platform, may cause problems when you try to write to protected keys.
Also to consider is how the Addon manager detects your new toolbar. It may be that if the Addon manager does not know about your new toolbar that it will stop it from being loaded by IE. But I don't know this for sure... I think it builds a list of Addons each time IE is started by inpecting the above keys and others under Software\Microsoft\Internet Explorer.
There is also a limit of 16 toolbar addons that you can have installed in IE. When you install any more they will not appear in the View>Toolbars list and cannot be displayed by the showbrowserbar method.
Your toolbar will not be visible in the IE toolbar until the user has choosen to show it from the View>Toolbars menu (or selected it from the toolbar context menu). Usually installers open a web page of instructions on how to display their toolbar once the installation process has finished.
Regards.