diff --git a/invesalius/data/trackers.py b/invesalius/data/trackers.py
index 20bc1a4..b86482e 100644
--- a/invesalius/data/trackers.py
+++ b/invesalius/data/trackers.py
@@ -152,7 +152,7 @@ def PolhemusTracker(tracker_id):
     except:
         trck_init = None
         lib_mode = 'error'
-        print('Could not connect to Polhemus.')
+        print('Could not connect to Polhemus by any method.')
 
     return trck_init, lib_mode
 
@@ -182,10 +182,10 @@ def PlhWrapperConnection(tracker_id):
                 sleep(0.175)
         else:
             trck_init = None
-            print('Could not connect to Polhemus via wrapper without error.')
+            print('Could not connect to Polhemus via wrapper without error: Initialize is False.')
     except:
         trck_init = None
-        print('Could not connect to Polhemus via wrapper with error.')
+        print('Could not connect to Polhemus via wrapper without error: Import failed.')
 
     return trck_init
 
diff --git a/invesalius/data/trigger.py b/invesalius/data/trigger.py
index f17fb9f..fefb34f 100644
--- a/invesalius/data/trigger.py
+++ b/invesalius/data/trigger.py
@@ -43,7 +43,8 @@ class Trigger(threading.Thread):
             self.COM = True
 
         except:
-            wx.MessageBox(_('Connection with port COM1 failed'), _('Communication error'), wx.OK | wx.ICON_ERROR)
+            #wx.MessageBox(_('Connection with port COM1 failed'), _('Communication error'), wx.OK | wx.ICON_ERROR)
+            print("Trigger init error: Connection with port COM1 failed")
             self.COM = False
 
         self._pause_ = False
@@ -61,7 +62,7 @@ class Trigger(threading.Thread):
     def run(self):
         while self.nav_id:
             if self.COM:
-                self.trigger_init.write('0')
+                self.trigger_init.write(b'0')
                 sleep(0.3)
                 lines = self.trigger_init.readlines()
                 # Following lines can simulate a trigger in 3 sec repetitions
--
libgit2 0.21.2