diff --git a/resources/templates/provision/polycom/4.x/{$mac}.cfg b/resources/templates/provision/polycom/4.x/{$mac}.cfg
index 039eb1fe4f..02d08e816c 100644
--- a/resources/templates/provision/polycom/4.x/{$mac}.cfg
+++ b/resources/templates/provision/polycom/4.x/{$mac}.cfg
@@ -14,7 +14,7 @@
 		reg.{$row.line_number}.thirdPartyName=""
 		reg.{$row.line_number}.auth.userId="{$row.user_id}"
 		reg.{$row.line_number}.auth.password="{$row.password}"
-		reg.{$row.line_number}.lineKeys="{$line_key_value_{$row.line_number}}"
+		{if isset($line_key_value_{$row.line_number})}reg.{$row.line_number}.lineKeys="{$line_key_value_{$row.line_number}}"{else}reg.{$row.line_number}.lineKeys="1"{/if}
 		{if isset($row.outbound_proxy)}reg.{$row.line_number}.outboundProxy.address = "{$row.outbound_proxy}"{/if}
 		{if isset($row.sip_port)}reg.{$row.line_number}.outboundProxy.port="{$row.sip_port}"{else}reg.{$row.line_number}.outboundProxy.port="5060"{/if}