Citrix Virtual Apps and Desktops

Configure COM Port and LPT Port Redirection settings using the registry

In VDA versions 7.0 through 7.8, COM Port and LPT Port settings are only configurable using the registry. For VDA versions earlier than 7.0 and for VDA versions 7.9 and later, these settings are configurable in Studio. For more information, see Port redirection policy settings and Bandwidth policy settings.

Policy settings for COM Port and LPT Port Redirection are located under HKLM\Software\Citrix\GroupPolicy\Defaults\Deprecated on the VDA image or machine.

To enable COM port and LPT port redirection, add new registry keys of type REG_DWORD, as follows:

Caution: Editing the registry incorrectly can cause serious problems that might require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. Be sure to back up the registry before you edit it.

Registry key Description Permitted values
AllowComPortRedirection Allow or prohibit COM port redirection 1 (Allow) or 0 (Prohibit)
LimitComBw Bandwidth limit for COM port redirection channel Numeric value
LimitComBWPercent Bandwidth limit for COM port redirection channel as a percentage of total session bandwidth Numeric value between 0 and 100
AutoConnectClientComPorts Automatically connect COM ports from the user device 1 (Allow) or 0 (Prohibit)
AllowLptPortRedirection Allow or prohibit LPT port redirection 1 (Allow) or 0 (Prohibit)
LimitLptBw Bandwidth limit for LPT port redirection channel Numeric value
LimitLptBwPercent Bandwidth limit for LPT port redirection channel as a percentage of total session bandwidth Numeric value between 0 and 100
AutoConnectClientLptPorts Automatically connect LPT ports from the user device 1 (Allow) or 0 (Prohibit)

After configuring these settings, change your machine catalogs to use the new master image or updated physical machine. Desktops are updated with the new settings the next time users log off.

Configure COM Port and LPT Port Redirection settings using the registry

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