Don't delete task, it'll be done after execution anyway

WAPT/control

@@ -1,5 +1,5 @@
 package           : fws-backuppc-agent
-version           : 1.3.4-19
+version           : 1.3.4-20
 architecture      : all
 section           : base
 priority          : optional

setup.py

@@ -75,7 +75,7 @@ def install():
     print('Deploying ssh keys through a scheduled task')
     run(r'schtasks /Create /SC ONCE /TN "deploy_backup_ssh_keys" /TR  "%s\deploy_keys.bat" /ST "%s" /RU lbkp /RP %s /F /V1 /Z' % (install_dir, time.strftime('%H:%M:%S',time.localtime(time.time() + 120)), variables['backup_pass']))
     run_task('deploy_backup_ssh_keys')
-    delete_task('deploy_backup_ssh_keys')
+    #delete_task('deploy_backup_ssh_keys')
 
 
 def uninstall():