diff --git a/package-lock.json b/package-lock.json
index 1530d95d..638e1d98 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "berlin-lea-performance-monitor",
-  "version": "1.11.3",
+  "version": "1.12.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "berlin-lea-performance-monitor",
-      "version": "1.11.3",
+      "version": "1.12.0",
       "dependencies": {
         "chart.js": "^3.9.1",
         "chartjs-adapter-moment": "^1.0.1",
diff --git a/package.json b/package.json
index df1fca7a..0538d1fd 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "berlin-lea-performance-monitor",
-  "version": "1.11.3",
+  "version": "1.12.0",
   "author": "David Leclerc",
   "main": "./src/index.ts",
   "scripts": {
diff --git a/src/models/sessions/SessionHistory.ts b/src/models/sessions/SessionHistory.ts
index e1646ec6..25b9711e 100644
--- a/src/models/sessions/SessionHistory.ts
+++ b/src/models/sessions/SessionHistory.ts
@@ -2,6 +2,7 @@ import { WEEKDAYS, WORKDAYS } from '../../constants/times';
 import logger from '../../logger';
 import { VersionedData, Weekday } from '../../types';
 import { toCountsFromArray, unique } from '../../utils/array';
+import { isKnownEvent } from '../../utils/event';
 import { formatDateForFilename, getWeekday } from '../../utils/locale';
 import { sum } from '../../utils/math';
 import TimeDuration from '../TimeDuration';
@@ -38,9 +39,10 @@ class SessionHistory {
     }
 
     public summarize() {
-        const errorCounts = this.getErrorCounts();
-        const successTimes = this
-            .getSuccesses()
+        const knownErrorCounts = this.getErrorCounts(isKnownEvent);
+        const unknownErrorCounts = this.getErrorCounts(err => !isKnownEvent(err));
+        
+        const successTimes = this.getSuccesses()
             .map(session => formatDateForFilename(session.getEndTime()));
 
         if (successTimes.length > 0) {
@@ -49,10 +51,11 @@ class SessionHistory {
             logger.info(`There was never an appointment available.`);
         }
 
-        if (sum(Object.values(errorCounts)) > 0) {
-            logger.info(errorCounts, `Errors encountered:`);
-        } else {
-            logger.info(`There was no error encountered.`);
+        if (sum(Object.values(knownErrorCounts)) > 0) {
+            logger.info(knownErrorCounts, `Known errors encountered:`);
+        }
+        if (sum(Object.values(unknownErrorCounts)) > 0) {
+            logger.info(unknownErrorCounts, `Unknown errors encountered:`);
         }
     }
 
@@ -182,8 +185,8 @@ class SessionHistory {
         return unique(this.getErrors(errorFilter));
     }
 
-    public getErrorCounts() {
-        return toCountsFromArray(this.getErrors());
+    public getErrorCounts(errorFilter: EventFilter = () => true) {
+        return toCountsFromArray(this.getErrors(errorFilter));
     }
 }
 
diff --git a/src/models/sessions/SessionHistoryBuilder.ts b/src/models/sessions/SessionHistoryBuilder.ts
index ffb047e5..85fb6c80 100644
--- a/src/models/sessions/SessionHistoryBuilder.ts
+++ b/src/models/sessions/SessionHistoryBuilder.ts
@@ -67,7 +67,7 @@ class SessionHistoryBuilder {
                 const errorCount = session.getErrors().length;
                 if (errorCount > 1) {
                     const sessionStartLine = session.getLogs()[0].line;
-                    logger.warn(`Invalid session [@${sessionStartLine}] with ${errorCount} errors found (there should only be one)`);
+                    logger.warn(`Invalid session [${session.getStartTime()} @${sessionStartLine}] with ${errorCount} > 1 errors found`);
                     return;
                 }