Pro edition. The FSLogix Rules page builds FSLogix App Masking rule sets and exports them as .fxr / .fxa file pairs. The files are compatible with Microsoft’s FSLogix Rule Editor.
What App Masking does #
App Masking hides, redirects or changes files, folders, registry keys, fonts and printers per user or group on shared session hosts (AVD, multi-session Windows). The rules are installed on the host, and the assignments decide who they apply to.
Creating a rule set #
| Option | Description |
|---|---|
| New Rule Set | Start from scratch |
| New from installed app… | Pick an installed application. A starter set is created that hides its install folder, uninstall registry key and Start menu shortcuts. Review it and add more rules if needed. |
| Import… | Load existing .fxr and/or .fxa files. Unsupported legacy rule types are skipped with a warning. |
Rules tab #
For each rule:
- Choose the Action:
- Hide
- Redirect
- Set registry value
- Choose the Item type:
- folder or registry key
- file or registry value
- font
- printer
- Enter the Source path, for example
C:\Program Files\MyApp\config.iniorHKLM\SOFTWARE\Contoso\App.- Use Insert macro for FSLogix path macros such as
%ProgramFilesFolder64%. - A
*wildcard matches one complete path part only.C:\Users\*\AppDataworks,C:\App*\does not.
- Use Insert macro for FSLogix path macros such as
- Fill in the extra fields for the action:
- Redirect: the destination path, and optionally Copy original first.
- Set registry value: the value type (String, ExpandableString, DWord, QWord or MultiString) and the data.
- Optionally add a Comment.
Bulk add: paste many paths, one per line, to create a hiding rule for each at once.
Errors such as an empty path prevent saving. Warnings point out risky entries, for example hiding important Windows folders.
Assignments tab #
Assignments decide who the rule set applies to. They are read from top to bottom, and the last matching entry wins.
A new rule set starts as Everyone / Doesn’t apply, which means it applies to nobody. The editor warns you until you add an assignment that applies.
- Who: Everyone, User, Group (by SID), Process, Network, Computer, OU or Environment variable.
- Applies / Doesn’t apply for each entry.
- Use the arrows to change the order.
- Presets:
- Apply to everyone
- Apply to group, exempt administrators
User and group assignments need identities synchronised from Active Directory. Cloud-only Entra ID accounts are not supported.
Preview tab #
Shows the exact .fxr and .fxa file contents and updates as you edit.
Exporting and deploying #
Click Download on a rule set:
- In the app: the files are saved to your Default Output Folder.
- In a browser: you get a ZIP with both files.
To deploy the rules:
- Copy both files to
C:\Program Files\FSLogix\Apps\Ruleson each session host, for example via your golden image, Intune, Group Policy or a PSADT package. - FSLogix picks them up immediately. No restart is needed.
- To remove the rules, delete the file pair.
Renaming a rule set only affects future exports. Files you exported earlier are not renamed.