diff --git a/lib/core/common.py b/lib/core/common.py
index 2fbd84ea3..a78703440 100755
--- a/lib/core/common.py
+++ b/lib/core/common.py
@@ -2739,7 +2739,7 @@ def decodeIntToUnicode(value):
 
 def unhandledExceptionMessage():
     """
-    Returns detailed message about occured unhandled exception
+    Returns detailed message about occurred unhandled exception
     """
 
     errMsg = "unhandled exception in %s, retry your " % VERSION_STRING
@@ -3372,7 +3372,7 @@ def evaluateCode(code, variables=None):
     except KeyboardInterrupt:
         raise
     except Exception, ex:
-        errMsg = "an error occured while evaluating provided code ('%s'). " % ex
+        errMsg = "an error occurred while evaluating provided code ('%s'). " % ex
         raise SqlmapGenericException(errMsg)
 
 def serializeObject(object_):
diff --git a/lib/core/option.py b/lib/core/option.py
index c29c55e28..a9648bde9 100644
--- a/lib/core/option.py
+++ b/lib/core/option.py
@@ -495,7 +495,7 @@ def _setCrawler():
                     status = '%d/%d links visited (%d%%)' % (i + 1, len(targets), round(100.0 * (i + 1) / len(targets)))
                     dataToStdout("\r[%s] [INFO] %s" % (time.strftime("%X"), status), True)
             except Exception, ex:
-                errMsg = "problem occured while crawling at '%s' ('%s')" % (target, ex)
+                errMsg = "problem occurred while crawling at '%s' ('%s')" % (target, ex)
                 logger.error(errMsg)
 
 def _setGoogleDorking():
@@ -625,7 +625,7 @@ def _findPageForms():
                     status = '%d/%d links visited (%d%%)' % (i + 1, len(targets), round(100.0 * (i + 1) / len(targets)))
                     dataToStdout("\r[%s] [INFO] %s" % (time.strftime("%X"), status), True)
             except Exception, ex:
-                errMsg = "problem occured while searching for forms at '%s' ('%s')" % (target, ex)
+                errMsg = "problem occurred while searching for forms at '%s' ('%s')" % (target, ex)
                 logger.error(errMsg)
 
 def _setDBMSAuthentication():
diff --git a/lib/core/threads.py b/lib/core/threads.py
index 0d924f5eb..f511d8709 100644
--- a/lib/core/threads.py
+++ b/lib/core/threads.py
@@ -140,7 +140,7 @@ def runThreads(numThreads, threadFunction, cleanupFunction=None, forwardExceptio
             try:
                 thread.start()
             except threadError, errMsg:
-                errMsg = "error occured while starting new thread ('%s')" % errMsg
+                errMsg = "error occurred while starting new thread ('%s')" % errMsg
                 logger.critical(errMsg)
                 break
 
diff --git a/lib/request/comparison.py b/lib/request/comparison.py
index 2db1e8975..b76ac9f55 100644
--- a/lib/request/comparison.py
+++ b/lib/request/comparison.py
@@ -90,7 +90,7 @@ def _comparison(page, headers, code, getRatioValue, pageLength):
 
     if kb.nullConnection and pageLength:
         if not seqMatcher.a:
-            errMsg = "problem occured while retrieving original page content "
+            errMsg = "problem occurred while retrieving original page content "
             errMsg += "which prevents sqlmap from continuation. Please rerun, "
             errMsg += "and if the problem persists turn off any optimization switches"
             raise SqlmapNoneDataException(errMsg)
diff --git a/lib/request/connect.py b/lib/request/connect.py
index 7a964d84d..060d52ac3 100644
--- a/lib/request/connect.py
+++ b/lib/request/connect.py
@@ -434,7 +434,7 @@ class Connect(object):
                         conn.fp._sock.close()
                     conn.close()
                 except Exception, msg:
-                    warnMsg = "problem occured during connection closing ('%s')" % msg
+                    warnMsg = "problem occurred during connection closing ('%s')" % msg
                     logger.warn(warnMsg)
 
         except urllib2.HTTPError, e:
diff --git a/lib/request/httpshandler.py b/lib/request/httpshandler.py
index 0f32385b6..4b18c5f62 100644
--- a/lib/request/httpshandler.py
+++ b/lib/request/httpshandler.py
@@ -54,7 +54,7 @@ class HTTPSConnection(httplib.HTTPSConnection):
                 else:
                     sock.close()
             except ssl.SSLError, errMsg:
-                logger.debug("SSL connection error occured ('%s')" % errMsg)
+                logger.debug("SSL connection error occurred ('%s')" % errMsg)
 
         if not success:
             raise SqlmapConnectionException("can't establish SSL connection")