diff --git a/linkcheck/log/CSVLogger.py b/linkcheck/log/CSVLogger.py
index be16b6ff..22de2fbe 100644
--- a/linkcheck/log/CSVLogger.py
+++ b/linkcheck/log/CSVLogger.py
@@ -66,7 +66,7 @@ class CSVLogger (StandardLogger):
     def newUrl (self, urlData):
         if self.fd is None: return
         row = [urlData.urlName, urlData.recursionLevel,
-               url_quote(urlData.parentName), urlData.baseRef,
+               url_quote(urlData.parentName or ""), urlData.baseRef,
                urlData.errorString, urlData.validString,
                urlData.warningString, urlData.infoString,
                urlData.valid, url_quote(urlData.url),
diff --git a/linkcheck/log/ColoredLogger.py b/linkcheck/log/ColoredLogger.py
index af0c9b78..e54fdf5e 100644
--- a/linkcheck/log/ColoredLogger.py
+++ b/linkcheck/log/ColoredLogger.py
@@ -49,7 +49,8 @@ class ColoredLogger (StandardLogger):
                         self.fd.write("o\n")
                     self.fd.write("\n"+self.field("parenturl")+
                               self.spaces("parenturl")+
-		              self.colorparent+url_quote(urlData.parentName)+
+		              self.colorparent+
+                              url_quote(urlData.parentName or "")+
 			      self.colorreset+"\n")
                     self.currentPage = urlData.parentName
                     self.prefix = 1
diff --git a/linkcheck/log/HtmlLogger.py b/linkcheck/log/HtmlLogger.py
index c6ef2569..761b4fe0 100644
--- a/linkcheck/log/HtmlLogger.py
+++ b/linkcheck/log/HtmlLogger.py
@@ -86,8 +86,8 @@ class HtmlLogger (StandardLogger):
         if urlData.parentName and self.has_field("parenturl"):
             self.fd.write("<tr>\n<td>"+self.field("parenturl")+
                '</td>\n<td><a target="top" href="'+
-               url_quote(urlData.parentName)+'">'+
-               url_quote(urlData.parentName)+"</a>")
+               url_quote(urlData.parentName or "")+'">'+
+               url_quote(urlData.parentName or "")+"</a>")
             if urlData.line:
                 self.fd.write(i18n._(", line %d")%urlData.line)
             if urlData.column:
diff --git a/linkcheck/log/SQLLogger.py b/linkcheck/log/SQLLogger.py
index 477d5c03..3bf227f3 100644
--- a/linkcheck/log/SQLLogger.py
+++ b/linkcheck/log/SQLLogger.py
@@ -53,7 +53,7 @@ class SQLLogger (StandardLogger):
 	      (self.dbname,
 	       StringUtil.sqlify(urlData.urlName),
                urlData.recursionLevel,
-	       StringUtil.sqlify(url_quote(urlData.parentName)),
+	       StringUtil.sqlify(url_quote(urlData.parentName or "")),
                StringUtil.sqlify(urlData.baseRef),
                StringUtil.sqlify(urlData.errorString),
                StringUtil.sqlify(urlData.validString),
diff --git a/linkcheck/log/StandardLogger.py b/linkcheck/log/StandardLogger.py
index 9e1b7cf5..57e96509 100644
--- a/linkcheck/log/StandardLogger.py
+++ b/linkcheck/log/StandardLogger.py
@@ -94,7 +94,7 @@ __init__(self, **args)
                           urlData.name+"\n")
         if urlData.parentName and self.has_field('parenturl'):
             self.fd.write(self.field('parenturl')+self.spaces("parenturl")+
-	                  url_quote(urlData.parentName)+
+	                  url_quote(urlData.parentName or "")+
                           (i18n._(", line %d")%urlData.line)+
                           (i18n._(", col %d")%urlData.column)+"\n")
         if urlData.baseRef and self.has_field('base'):