diff --git a/lib/request/connect.py b/lib/request/connect.py
index de08de709..2bdb80f4e 100644
--- a/lib/request/connect.py
+++ b/lib/request/connect.py
@@ -262,6 +262,7 @@ class Connect:
             else:
                 debugMsg = "got HTTP error code: %d (%s)" % (code, status)
                 logger.debug(debugMsg)
+                return page, responseHeaders
 
         except (urllib2.URLError, socket.error, socket.timeout, httplib.BadStatusLine, httplib.IncompleteRead), e:
             tbMsg = traceback.format_exc()
diff --git a/plugins/dbms/mssqlserver/enumeration.py b/plugins/dbms/mssqlserver/enumeration.py
index de6a2a8b1..9955c3f6c 100644
--- a/plugins/dbms/mssqlserver/enumeration.py
+++ b/plugins/dbms/mssqlserver/enumeration.py
@@ -9,6 +9,7 @@ See the file 'doc/COPYING' for copying permission
 
 from lib.core.agent import agent
 from lib.core.common import getRange
+from lib.core.common import isNumPosStrValue
 from lib.core.data import conf
 from lib.core.data import kb
 from lib.core.data import logger
@@ -79,7 +80,7 @@ class Enumeration(GenericEnumeration):
                 query = rootQuery.blind.count % db
                 count = inject.getValue(query, inband=False, charsetType=2)
 
-                if not count.isdigit() or not len(count) or count == "0":
+                if not isNumPosStrValue(count):
                     warnMsg  = "unable to retrieve the number of "
                     warnMsg += "tables for database '%s'" % db
                     logger.warn(warnMsg)
@@ -163,7 +164,7 @@ class Enumeration(GenericEnumeration):
                     query += " AND %s" % tblQuery
                     count = inject.getValue(query, inband=False, expected=EXPECTED.INT, charsetType=2)
 
-                    if not count.isdigit() or not len(count) or count == "0":
+                    if not isNumPosStrValue(count):
                         warnMsg = "no table"
                         if tblConsider == "1":
                             warnMsg += "s like"
@@ -268,7 +269,7 @@ class Enumeration(GenericEnumeration):
                     query += " AND %s" % colQuery.replace("[DB]", db)
                     count = inject.getValue(query, inband=False, expected=EXPECTED.INT, charsetType=2)
 
-                    if not count.isdigit() or not len(count) or count == "0":
+                    if not isNumPosStrValue(count):
                         warnMsg = "no tables contain column"
                         if colConsider == "1":
                             warnMsg += "s like"
diff --git a/plugins/dbms/mssqlserver/filesystem.py b/plugins/dbms/mssqlserver/filesystem.py
index e27f63a8b..fc77ddca8 100644
--- a/plugins/dbms/mssqlserver/filesystem.py
+++ b/plugins/dbms/mssqlserver/filesystem.py
@@ -12,6 +12,7 @@ import ntpath
 import os
 
 from lib.core.common import getRange
+from lib.core.common import isNumPosStrValue
 from lib.core.common import posixToNtSlashes
 from lib.core.common import randomStr
 from lib.core.data import conf
@@ -97,7 +98,7 @@ class Filesystem(GenericFilesystem):
             result = []
             count  = inject.getValue("SELECT COUNT(%s) FROM %s" % (self.tblField, hexTbl), resumeValue=False, charsetType=2)
 
-            if not count.isdigit() or not len(count) or count == "0":
+            if not isNumPosStrValue(count):
                 errMsg  = "unable to retrieve the content of the "
                 errMsg += "file '%s'" % rFile
                 raise sqlmapNoneDataException(errMsg)
diff --git a/plugins/dbms/oracle/enumeration.py b/plugins/dbms/oracle/enumeration.py
index a0c795a2c..d3ff74c62 100644
--- a/plugins/dbms/oracle/enumeration.py
+++ b/plugins/dbms/oracle/enumeration.py
@@ -9,6 +9,7 @@ See the file 'doc/COPYING' for copying permission
 
 from lib.core.agent import agent
 from lib.core.common import getRange
+from lib.core.common import isNumPosStrValue
 from lib.core.data import conf
 from lib.core.data import kb
 from lib.core.data import logger
@@ -118,7 +119,7 @@ class Enumeration(GenericEnumeration):
                     query = rootQuery.blind.count % queryUser
                 count = inject.getValue(query, inband=False, expected=EXPECTED.INT, charsetType=2)
 
-                if not count.isdigit() or not len(count) or count == "0":
+                if not isNumPosStrValue(count):
                     if not count.isdigit() and not query2:
                         infoMsg = "trying with table USER_SYS_PRIVS"
                         logger.info(infoMsg)
@@ -240,7 +241,7 @@ class Enumeration(GenericEnumeration):
                     query += " WHERE %s" % colQuery
                     count = inject.getValue(query, inband=False, expected=EXPECTED.INT, charsetType=2)
 
-                    if not count.isdigit() or not len(count) or count == "0":
+                    if not isNumPosStrValue(count):
                         warnMsg = "no tables contain column"
                         if colConsider == "1":
                             warnMsg += "s like"