Outlook form cache problem

[Frohut]

In the company where I work, we use custom forms without code.



The custom forms are used as a forced form when a new appointment or meeting
request is made in a resource calendar (in a public folder).

When an existing appointment is opened, most of the time the form is showed.
However several times a week there is a problem with the form cache and the
default appointment form is displayed instead of the custom form.

The problems occur when the user has opened multiple appointments in the
same resource calendar. The custom forms in other resource calendars are
still available for this user.



The Outlook form cache of the user looks something like this:

Local Settings

Application Data

Microsoft

Forms

IPM.Appointment.room1

IPM.Appointment.room10

IPM.Appointment.room100

IPM.Appointment.room1000

IPM.Appointment.room10000

IPM.Appointment.room100000

IPM.Appointment.room2

IPM.Appointment.room20

IPM.Appointment.room200

IPM.Appointment.room2000

IPM.Appointment.room20000

IPM.Appointment.room200000

IPM.Appointment.room3

IPM.Appointment.room4

IPM.Appointment.room40

IPM.Appointment.room400

IPM.Appointment.room4000



There are several knowledge articles and information on the internet about
Outlook form cache problems and till now I try to resolve the problem with
the following solutions:

- Republish the forms

- Raise the form cache to 4096

- Change a form to an one-off form

- Add the ForceFormReload key in the register



None of these solutions above have solved the problem.

The problem can be solved by clearing the form cache in Outlook or deleting
the directory Form in the user profile.



The user works with thin client in a TS (Citrix) environment with mandatory
profiles.



Any suggestions to resolve this cache problem?