Correct exception generated when no service pack is present

SystemInformation.py

@@ -33,7 +33,6 @@ class SystemInformation:
         for part in self._disk_c():
             hdd.append('{} {:.2f}GB free'.format(part[0], part[1]/(1024**3)))
         self.hdFree = 'HDD:\t{}'.format(', '.join(hdd))
-        # self.hdFree = 'HDD:\t{:.2f}GB free'.format(self._disk_c()/(1024**3))
         self.os = 'OS:\t{}'.format(self._os_version())
 
     def _cpu(self):
@@ -115,7 +114,10 @@ class SystemInformation:
         try:
             sp = get('CSDVersion')
         except:
-            sp = get('CSDBuildNumber')
+            try:
+                sp = 'n' + get('CSDBuildNumber')
+            except:
+                sp = '(no service pack found)'
         build = get('CurrentBuildNumber')
         return '{} {} (build {})'.format(os, sp, build)