Environment Manager Engineering Setting - Exceptions (AsVfxLdr.sys)

Version 1

    Verified Product Versions

    Environment Manager 8.5Environment Manager 8.4Environment Manager 8.2Environment Manager 8.1Environment Manager 8.3Environment Manager 8.0


    You wish to exclude certain processes from triggering process start/stop actions, being personalized or simply ensuring Environment Manager does not interact with a given process, such as injecting EmLoader.dll or PVC.dll.

    You may also wish to exclude short-lived, high frequency processes, such as Citrix Health Monitoring processes, Windows Search indexing, AV Components etc.


    Environment Manager uses two drivers, AsVfxLdr.sys and EmDriver.sys.

    AsVfxLdr.sys detects any user processes starting, and loads EmLoader.dll into the process, which in turn talks to the EmUser.exe process within the session to determine if any other DLLs need to be loaded, such as:

    • PVC.dll (for applications managed via User Personalization)
    • LockdownMgr.dll (for General Lockdown actions)

    The Exceptions engineering setting was added to Environment Manager 8.0.959.0 and above to allow processes to be excluded from AsVfxLdr.sys (see the "See Also" section below for the technote regarding EmDriver's equivalent "ProcessWhiteList" engineering setting).

    Prior to Environment Manager, this setting only allowed process names to be added, from onwards, drives, paths and filepaths can also be added, for example:

    • PATH
    • PATH\binary.name
    • Binary.name
    • D:


    AppSense Product:        Environment Manager


    Engineering Settings:   


    Introduced (Agent):      Environment Manager 8.0.959.0


    Deprecated (Agent):      N/A


    Introduced (Console):    N/A


    Deprecated (Console):    N/A

    Note - Certain common engineering settings have been made configurable via the "Custom Settings" option within the Environment Manager Console (only applicable to and later)

    Valid Registry Hives (* = highest priority, where applicable):






    8.0.x.x Registry Key:    \Software\AppSense Technologies\AsVfxLdr


    8.1.x.x + Registry Key:  \Software\AppSense\AsVfxLdr


    Registry Value Name:     Exceptions


    Registry Value Type:     REG_MULTI_SZ


    Registry Value Data:     List of filenames (or additionally paths depending on agent version)


    Default (if not set):    Various entries are entered by default, depending on Agent version


    When using file paths / folders, variables may not be used as the driver cannot expand these.

    The ability to use paths / drives, whilst being added to AsVfxLdr's Exceptions setting in, was not added to EmDriver's ProcessWhiteList until onwards.

    See Also

    • TN-150953 - Environment Manager Engineering Setting - ProcessWhiteList (EmDriver.sys)
    • TN-150759 - EmSystem high CPU (and Memory) usage on Server 2008 R2 sp1 with XenApp 6.x, McAfee and EM 8.3
    • TN-150895 - Removed EM process exclusion causes EmDriver to stall critical EM processes leading to system hang.
    • TN-150930 - Process start / stop Desktop Settings Snapshot & Refresh during logon causes delays
    • TN-150728 - Recommended Anti-Virus/AppSense Exclusions
    • TN-150792 - XenDesktop performance & failing / hanging logoff