diff --git a/iprbench/envmodules.py b/iprbench/envmodules.py
index 2cb0a0b..1e917d0 100644
--- a/iprbench/envmodules.py
+++ b/iprbench/envmodules.py
@@ -21,8 +21,12 @@ def get_available_modules() -> Set[EnvModule]:
     # module-info
     # modules
     # null
+    logging.debug('get_available_modules: completed_process.stdout="%s"', completed_process.stdout)
+    logging.debug('get_available_modules: completed_process.sterr="%s"', completed_process.stderr)
     stdout = completed_process.stdout.decode('utf-8')
     logging.debug('get_available_modules: stdout="%s"', stdout)
+    stderr = completed_process.stderr.decode('utf-8')
+    logging.debug('get_available_modules: stderr="%s"', stderr)
     for line in stdout.splitlines():
         logging.debug('available module line: "%s"', line)
         if not re.search(r'\:$', line):  # ignore the directories such as '/usr/share/modules/modulefiles:'