# Antivirus Exclusions

Installing antivirus software on an RD Session Host server greatly affects overall system performance, especially the CPU usage. We highly recommend that you exclude all folders that hold temporary files from the active monitoring list, especially folders generated by services and other system components.

The Parallels RAS folder to be excluded from real-time scanning is `%programfiles(x86)%\Parallels\ApplicationServer`.

For Parallels RAS port reference, please refer to **Parallels Remote Application Server Administrator's Guide**, which can be downloaded from <http://www.parallels.com/products/ras/resources>. For additional information, please also see <http://kb.parallels.com/124003>.

The Parallels Client for Windows folder to be excluded from real-time scanning is as follows:

* 32-bit: `%programfiles(x86)%\Parallels\Client`
* 64-bit: `%programfiles%\Parallels\Client`

Parallels recommends to exclude the above Parallels RAS and Parallels Client for Windows folders from real-time or on-access scanning and scan them on a regular basis using scheduled scans. You should also monitor the creation of new files in the excluded folders.

## **FSLogix anti-virus exclusions**

For FSLogix Profile Container to work properly, configure your antivirus to exclude the following objects, as per Microsoft’s recommendations:

**Files:**

* %TEMP%\\\*\\\*.VHD
* %TEMP%\\\*\\\*.VHDX
* %Windir%\TEMP\\\*\\\*.VHD
* %Windir%\TEMP\\\*\\\*.VHDX
* \\\server-name\share-name\\\*\\\*.VHD
* \\\server-name\share-name\\\*\\\*.VHD.lock
* \\\server-name\share-name\\\*\\\*.VHD.meta
* \\\server-name\share-name\\\*\\\*.VHD.metadata
* \\\server-name\share-name\\\*\\\*.VHDX
* \\\server-name\share-name\\\*\\\*.VHDX.lock
* \\\server-name\share-name\\\*\\\*.VHDX.meta
* \\\server-name\share-name\\\*\\\*.VHDX.metadata

**Cloud Cache specific exclusions:**

* %ProgramData%\FSLogix\Cache\ (folder and files)
* %ProgramData%\FSLogix\Proxy\\\* (folder and files)

{% hint style="info" %}
**Note:** Antivirus exclusions for Microsoft Defender for Endpoint (previously Microsoft Defender Advanced Threat Protection) can be set via Parallels RAS optimizations (Windows Defender ATP category). See this KB for more info: <https://kb.parallels.com/en/125071>.
{% endhint %}


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