Index: /trunk/src/VBox/HostServices/GuestProperties/service.cpp
===================================================================
--- /trunk/src/VBox/HostServices/GuestProperties/service.cpp	(revision 26748)
+++ /trunk/src/VBox/HostServices/GuestProperties/service.cpp	(revision 26749)
@@ -793,10 +793,13 @@
      */
     char pszPatterns[MAX_PATTERN_LEN];
-    for (unsigned i = 0; i < cchPatterns - 1; ++i)
-        if (pcchPatterns[i] != '\0')
-            pszPatterns[i] = pcchPatterns[i];
-        else
-            pszPatterns[i] = '|';
-    pszPatterns[cchPatterns - 1] = '\0';
+    if (RT_SUCCESS(rc))
+    {
+        for (unsigned i = 0; i < cchPatterns - 1; ++i)
+            if (pcchPatterns[i] != '\0')
+                pszPatterns[i] = pcchPatterns[i];
+            else
+                pszPatterns[i] = '|';
+        pszPatterns[cchPatterns - 1] = '\0';
+    }
 
     /*
@@ -827,5 +830,6 @@
         }
     }
-    buffer.append(4, '\0');  /* The final terminators */
+    if (RT_SUCCESS(rc))
+        buffer.append(4, '\0');  /* The final terminators */
 
     /*