The [Extensions] section lists the extended attributes of the form, typically a named property set, which are any attributes beyond the basic ones listed in the [Description] section of the form configuration file. Extended attributes are properties returned from calls to the GetProps method of the IMAPIFormInfo object with the high bit set in the property tag. Client applications can determine a form's extended attributes, if any, by retrieving these tags. To do so, clients call the IMAPIProp::GetIDsFromNames method, passing in the names of the form's properties and call the IMAPIProp::GetProps method to get the properties.
Each entry in the [Extensions] section references a subsequent section that has a name with the syntax [Extension.string2].
[Extensions]
Extension.string1 = string2
Each extension property section defines one extension attribute using the MAPI named property syntax. The property type must be either PT_LONG or PT_STRING8. Property sets containing named strings are not supported. The format of the [Extension] section is:
[Extension.string2]
Type = integer
NmidPropset = guid
NmidInteger = integer
Value = string | integer
An example of an [Extensions] section and a subsequent related section is shown following.
[Extensions]
Extension.A = 1
[Extension.1]
Type = 30
NmidPropset = {00020D0C-0000-0000-C000-000000000046}
NmidInteger = 1
Value = 11220000