Outlook Web Access : Client Cache with APM

Problem this snippet solves:

The iApp / Deployment guide suggest to disable App Cache for OWA when using F5 APM.

This irule provide a solution to prevent "Access policy evaluation is already in progress" page and keep cache App cache enabled.

How to use this snippet:

enable this irule on the exchange virtual server.

Code :

    set landinguri [ACCESS::session data get session.server.landinguri]
    switch -glob $landinguri {
        "/owa/plt1.ashx?*" -
        "/owa/sessiondata.ashx?appcacheclient=1" -
        "/owa/userspecificresourceinjector.ashx?*&appcacheclient=1*" -
        "/owa/manifests/appCacheManifestHandler.ashx?owamanifest=1" {
            ACCESS::respond 403 -version "1.1" noserver "Connection" "Close"
            ACCESS::session remove
Published Jan 26, 2017
Version 1.0

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  • Hi,


    I never use iApps, but deployment guide is useful.


    I posted this code here to share with all DC members. I hope Exchange iApp developper read this code and will validate to include it.


  • When verifying the config I am receiving the following warning:

    [The following errors were not caught before. Please correct the script in order to avoid future disruption. "unexpected end of arguments;expected argument spec:HEADER_VALUE"366 65][ACCESS::respond 403 -version "1.1" noserver "Connection" "Close"]

    Is it possible to avoid this warning by adding the HEADER_VALUE ?