c# - Windows service keeps on failing -

i have windows service designed continuously retrieve messages azure service bus queue , pass other queues.i have deployed service 1 of server computer unfortunately service keeps failing @ random time interval.

my application handles exceptions , writes them file.the main purpose of application hook queue , listen messages continuously , never move application stop stage.i'm using timer in application , don't think causing problem.i'd know best approach handle errors , make application stable, below code. in advance.

public partial class scheduler : servicebase {     private timer scheduletimer = null;      private string servicenamespace;     private string issuesecretkey;     private string sourcequeue;     private string destinationqueue;      public scheduler()     {         initializecomponent();     }      protected override void onstart(string[] args)     {         scheduletimer = new timer();         this.scheduletimer.interval = 1000;//1 sec         this.scheduletimer.elapsed += new system.timers.elapsedeventhandler(this.timer1_tick);         scheduletimer.enabled = true;         writetofile("application started : "+datetime.now.tostring());     }      protected void timer1_tick(object sender, elapsedeventargs e)     {         scheduletimer.enabled = false;         writetofile("business logic started : " + datetime.now.tostring());         //business logic code goes here     }       protected override void onstop()     {         scheduletimer.enabled = false;         writetofile("application stoped : "+datetime.now.tostring());     }      public void writetofile(string text)     {         string directory = appdomain.currentdomain.basedirectory;         string logfilepath = directory + "logfile.txt";           using (streamwriter writer = new streamwriter(logfilepath, true))         {             writer.writeline(text);             writer.close();         }     }      public void writeerrorstofile(exception ex)     {         string directory = appdomain.currentdomain.basedirectory;         string errorlogfilepath = directory + "errorlogfile.txt";          using (streamwriter writer = new streamwriter(errorlogfilepath, true))         {             writer.writeline("time occured: " + datetime.now.tostring());             writer.writeline(ex.message +" "+ datetime.now.tostring());             writer.close();         }     }