After starting the service using sysmail_start_sp run the following script. This will solve the issue

SET NOCOUNT ON

Declare @ch uniqueidentifier;

Declare @message_type nvarchar(256);

Declare @message_body nvarchar(max);

Declare @ctr bigint;

Declare @ctr2 bigint;

While (1=1)

Begin

Receive @ch = conversation_handle, @message_type = message_type_name from ExternalMailQueue

set @ctr2 = @ctr2 + 1

set @ctr = (select count(*) from ExternalMailQueue)

if @ctr = 0

break

end

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Allways think Positive

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