diff --git a/.gitignore b/.gitignore
index c7b6d033..baae0238 100644
--- a/.gitignore
+++ b/.gitignore
@@ -166,3 +166,5 @@ pip-log.txt
 
 # Mac crap
 .DS_Store
+
+*.code-workspace
\ No newline at end of file
diff --git a/QuickBooks/Cast.php b/QuickBooks/Cast.php
index d58f5c11..f97d3818 100755
--- a/QuickBooks/Cast.php
+++ b/QuickBooks/Cast.php
@@ -255,7 +255,7 @@ static public function cast($type_or_action, $field, $value, $use_abbrevs = true
 			$dh = opendir(dirname(__FILE__) . '/QBXML/Schema/Object');
 			while (false !== ($file = readdir($dh)))
 			{
-				if ($file{0} == '.' or substr($file, -6, 6) != 'Rq.php')
+				if ($file[0] == '.' or substr($file, -6, 6) != 'Rq.php')
 				{
 					continue;
 				}
diff --git a/QuickBooks/Driver/Sql/Mysqli.php b/QuickBooks/Driver/Sql/Mysqli.php
index fe856210..8cde5480 100644
--- a/QuickBooks/Driver/Sql/Mysqli.php
+++ b/QuickBooks/Driver/Sql/Mysqli.php
@@ -436,7 +436,7 @@ protected function _escape($str)
 			$str = '';
 		}
 
-		return $this->_conn->real_escape_string($str);
+		return $this->_conn->real_escape_string(isset($str) ? $str : '');
 	}
 
 	/**
diff --git a/QuickBooks/MerchantService/CheckingAccount.php b/QuickBooks/MerchantService/CheckingAccount.php
index ac0dd32d..7f7a6339 100644
--- a/QuickBooks/MerchantService/CheckingAccount.php
+++ b/QuickBooks/MerchantService/CheckingAccount.php
@@ -55,7 +55,7 @@ public function __construct($routing, $account, $info, $type, $first_name, $last
 		
 		$phone = trim(str_replace(array('(', ')', '+', ' ', '.', '-'), '', $phone));
 		if (strlen($phone) == 11 and 
-			$phone{0} == '1')
+			$phone[0] == '1')
 		{
 			$phone = substr($phone, 1);
 		}
diff --git a/QuickBooks/Utilities.php b/QuickBooks/Utilities.php
index c90ece51..9bbdbcde 100755
--- a/QuickBooks/Utilities.php
+++ b/QuickBooks/Utilities.php
@@ -91,7 +91,8 @@ static public function mask($message)
 			{
 				// It's an XML tag
 				$contents = QuickBooks_Utilities::_extractTagContents(trim($key, '<> '), $message);
-				
+
+				$contents = isset($contents) ? $contents : '';
 				$masked = str_repeat('x', min(strlen($contents), 12)) . substr($contents, 12);
 				
 				$message = str_replace($key . $contents . '</' . trim($key, '<> ') . '>', $key . $masked . '</' . trim($key, '<> ') . '>', $message);
diff --git a/QuickBooks/WebConnector/Handlers.php b/QuickBooks/WebConnector/Handlers.php
index 3348875d..722ed901 100755
--- a/QuickBooks/WebConnector/Handlers.php
+++ b/QuickBooks/WebConnector/Handlers.php
@@ -544,7 +544,7 @@ public function authenticate($obj)
 		$customauth_wait_before_next_update = null;
 		$customauth_min_run_every_n_seconds = null;
 
-		if (is_array($override_dsn) or strlen($override_dsn)) 	// Custom autj
+		if (is_array($override_dsn) or strlen(isset($override_dsn) ? $override_dsn : '')) 	// Custom autj
 		{
 			//if ($auth->authenticate($obj->strUserName, $obj->strPassword, $customauth_company_file, $customauth_wait_before_next_update, $customauth_min_run_every_n_seconds) and
 
diff --git a/QuickBooks/XML.php b/QuickBooks/XML.php
index b58ec3c5..c3577056 100755
--- a/QuickBooks/XML.php
+++ b/QuickBooks/XML.php
@@ -433,8 +433,7 @@ static public function decode($str, $for_qbxml = true)
 			'&quot;' => '"', 
 			'&amp;' => '&', 		// Make sure that this is *the last* transformation to run, otherwise we end up double-un-encoding things
 			);
-			
-		return str_replace(array_keys($transform), array_values($transform), $str);		
+
+		return str_replace(array_keys($transform), array_values($transform), isset($str) ? $str : '');
 	}
 }
-
diff --git a/QuickBooks/XML/Backend/Builtin.php b/QuickBooks/XML/Backend/Builtin.php
index 76849412..d5ddb704 100644
--- a/QuickBooks/XML/Backend/Builtin.php
+++ b/QuickBooks/XML/Backend/Builtin.php
@@ -376,7 +376,7 @@ protected function _parseHelper($xml, &$Root, &$errnum, &$errmsg, $indent = 0)
 				$Node->addAttribute($key, $value);
 			}
 			
-			if (false !== strpos($payload, '<'))
+			if (false !== strpos(isset($payload) ? $payload : '', '<'))
 			{
 				// The tag contains child tags