diff --git a/mailnews/base/src/nsMsgFolderCache.cpp b/mailnews/base/src/nsMsgFolderCache.cpp
index 9a57f245933..b3674f177b9 100644
--- a/mailnews/base/src/nsMsgFolderCache.cpp
+++ b/mailnews/base/src/nsMsgFolderCache.cpp
@@ -383,7 +383,11 @@ NS_IMETHODIMP nsMsgFolderCache::GetCacheElement(const char *pathKey, PRBool crea
 
 	if (!result || !pathKey)
 		return NS_ERROR_NULL_POINTER;
-
+		
+	if (nsCRT::strlen(pathKey) == 0) {
+		return NS_ERROR_FAILURE;
+	}
+	
 	nsCStringKey hashKey(pathKey);
 
 	*result = (nsIMsgFolderCacheElement *) m_cacheElements->Get(&hashKey);