diff --git a/www/admin/class_test.session.php b/www/admin/class_test.session.php
index 0f685e87..7cc610c2 100644
--- a/www/admin/class_test.session.php
+++ b/www/admin/class_test.session.php
@@ -78,16 +78,18 @@ if (isset($_SESSION)) {
 #
 print "[UNSET] To set session name valid: "
 	. ($session->checkValidSessionName($session_name) ? 'Valid' : 'Invalid') . "<br>";
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[FAILED] Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[SET] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[FAILED] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 // set again
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[2 FAILED] Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[2 SET] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[2 FAILED] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 print "[SET] Current session id: " . $session->getSessionId() . "<br>";
 print "[SET] Current session name: " . $session->getSessionName() . "<br>";
@@ -125,10 +127,11 @@ print "[READ MAGIC] unset Isset: " . (isset($session->setwrap) ? 'Yes' : 'No') .
 
 // differnt session name
 $session_name = 'class-test-session-ALT';
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[3 FAILED] Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[3 SET] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[3 FAILED] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 print "[SET AGAIN] Current session id: " . $session->getSessionId() . "<br>";
 
@@ -141,10 +144,11 @@ $_SESSION['will_never_be_written'] = 'empty';
 
 // open again
 $session_name = 'class-test-session';
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[4 FAILED] Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[4 SET] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[4 FAILED] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 print "[START AGAIN] Current session id: " . $session->getSessionId() . "<br>";
 $_SESSION['will_be_written_again'] = 'Full';
@@ -153,10 +157,11 @@ $_SESSION['will_be_written_again'] = 'Full';
 $session->writeClose();
 // invalid
 $session_name = '123';
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[5 FAILED] Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[5 SET] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[5 FAILED] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 print "[BAD NAME] Current session id: " . $session->getSessionId() . "<br>";
 print "[BAD NAME] Current session name: " . $session->getSessionName() . "<br>";
diff --git a/www/admin/class_test.session.read.php b/www/admin/class_test.session.read.php
index ec40f7c7..b871ea8c 100644
--- a/www/admin/class_test.session.read.php
+++ b/www/admin/class_test.session.read.php
@@ -69,16 +69,18 @@ print "[UNSET] Current session status: " . getSessionStatusString($session->getS
 
 print "[READ] " . $var . ": " . ($_SESSION[$var] ?? '{UNSET}') . "<br>";
 // start
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "Session start failed: " . $session->getErrorStr() . "<br>";
-} else {
-	print "Current session id: " . $session_id . "<br>";
+try {
+	$session_id = $session->startSession($session_name);
+	print "[1] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[1] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 // set again
-if (false === ($session_id = $session->startSession($session_name))) {
-	print "[2] Session start failed<br>";
-} else {
+try {
+	$session_id = $session->startSession($session_name);
 	print "[2] Current session id: " . $session_id . "<br>";
+} catch (\Exception $e) {
+	print "[2] Session start failed:<br>" . $e->getMessage() . "<br>" . $e . "<br>";
 }
 print "[SET] Current session id: " . $session->getSessionId() . "<br>";
 print "[SET] Current session name: " . $session->getSessionName() . "<br>";
diff --git a/www/lib/CoreLibs/Combined/DateTime.php b/www/lib/CoreLibs/Combined/DateTime.php
index fd6f84ef..286b8382 100644
--- a/www/lib/CoreLibs/Combined/DateTime.php
+++ b/www/lib/CoreLibs/Combined/DateTime.php
@@ -324,7 +324,7 @@ class DateTime
 	 * @return int                int -1 (s<e)/0 (s=e)/1 (s>e) as difference
 	 * @throws \UnexpectedValueException On empty start/end values
 	 */
-	public static function compareDate(string $start_date, string $end_date): int|bool
+	public static function compareDate(string $start_date, string $end_date): int
 	{
 		// pre check for empty or wrong
 		if ($start_date == '--' || $end_date == '--' || empty($start_date) || empty($end_date)) {
@@ -337,18 +337,20 @@ class DateTime
 		if (($end_timestamp = strtotime($end_date)) === false) {
 			throw new \UnexpectedValueException("Error parsing end date through strtotime()");
 		}
+		$comp = 0;
 		// convert anything to Y-m-d and then to timestamp
 		// this is to remove any time parts
 		$start_timestamp = strtotime(date('Y-m-d', $start_timestamp));
 		$end_timestamp = strtotime(date('Y-m-d', $end_timestamp));
 		// compare, or end with false
 		if ($start_timestamp < $end_timestamp) {
-			return -1;
+			$comp = -1;
 		} elseif ($start_timestamp == $end_timestamp) {
-			return 0;
+			$comp = 0;
 		} elseif ($start_timestamp > $end_timestamp) {
-			return 1;
+			$comp = 1;
 		}
+		return $comp;
 	}
 
 	/**
@@ -365,7 +367,7 @@ class DateTime
 	 * @return int                    -1 (s<e)/0 (s=e)/1 (s>e) as difference
 	 * @throws \UnexpectedValueException On empty start/end values
 	 */
-	public static function compareDateTime(string $start_datetime, string $end_datetime): int|bool
+	public static function compareDateTime(string $start_datetime, string $end_datetime): int
 	{
 		// pre check for empty or wrong
 		if ($start_datetime == '--' || $end_datetime == '--' || empty($start_datetime) || empty($end_datetime)) {
@@ -378,14 +380,16 @@ class DateTime
 		if (($end_timestamp = strtotime($end_datetime)) === false) {
 			throw new \UnexpectedValueException("Error parsing end timestamp through strtotime()");
 		}
+		$comp = 0;
 		// compare, or return false
 		if ($start_timestamp < $end_timestamp) {
-			return -1;
+			$comp = -1;
 		} elseif ($start_timestamp == $end_timestamp) {
-			return 0;
+			$comp = 0;
 		} elseif ($start_timestamp > $end_timestamp) {
-			return 1;
+			$comp = 1;
 		}
+		return $comp;
 	}
 
 	/**
diff --git a/www/lib/CoreLibs/Output/Image.php b/www/lib/CoreLibs/Output/Image.php
index a7d494fa..9d385117 100644
--- a/www/lib/CoreLibs/Output/Image.php
+++ b/www/lib/CoreLibs/Output/Image.php
@@ -292,12 +292,18 @@ class Image
 					// image, copy source image, offset in image, source x/y, new size, source image size
 					$thumb = imagecreatetruecolor($thumb_width_r, $thumb_height_r);
 					if ($thumb === false) {
-						return false;
+						throw new \RuntimeException(
+							'imagecreatetruecolor failed: ' . $thumbnail . ', ' . $filename,
+							1
+						);
 					}
 					if ($img_type == IMAGETYPE_PNG) {
 						$imagecolorallocatealpha = imagecolorallocatealpha($thumb, 0, 0, 0, 127);
 						if ($imagecolorallocatealpha === false) {
-							return false;
+							throw new \RuntimeException(
+								'imagecolorallocatealpha failed: ' . $thumbnail . ', ' . $filename,
+								2
+							);
 						}
 						// preservere transaprency
 						imagecolortransparent(
@@ -359,8 +365,10 @@ class Image
 						imagedestroy($source);
 						imagedestroy($thumb);
 					} else {
-						$exception_message = 'Invalid source image file. Only JPEG/PNG are allowed: ' . $filename;
-						$thumbnail = false;
+						throw new \RuntimeException(
+							'Invalid source image file. Only JPEG/PNG are allowed: ' . $filename,
+							3
+						);
 					}
 				}
 			} else {
@@ -401,14 +409,20 @@ class Image
 				}
 				$thumb = imagecreatetruecolor($thumb_width, $thumb_height);
 				if ($thumb === false) {
-					return false;
+					throw new \RuntimeException(
+						'imagecreatetruecolor dummy failed: ' . $thumbnail . ', ' . $filename,
+						3
+					);
 				}
 				// add outside border px = 5% (rounded up)
 				// eg 50px -> 2.5px
 				$gray = imagecolorallocate($thumb, 200, 200, 200);
 				$white = imagecolorallocate($thumb, 255, 255, 255);
 				if ($gray === false || $white === false) {
-					return false;
+					throw new \RuntimeException(
+						'imagecolorallocate/imagecolorallocate dummy failed: ' . $thumbnail . ', ' . $filename,
+						2
+					);
 				}
 				// fill gray background
 				imagefill($thumb, 0, 0, $gray);