diff --git a/boxmox/data.py b/boxmox/data.py
index e52fdc74284e8bb103e9e4b529ad59f5458ae089..46a7f879aed3018824c5540e5a09697381cb29be 100644
--- a/boxmox/data.py
+++ b/boxmox/data.py
@@ -15,6 +15,7 @@ def _mygenfromtxt(f):
         spamreader = csv.reader(f, dialect)
     except:
         warnings.warn('Could not determine dialect, falling back to default.')
+        f.seek(curpos)
         spamreader = csv.reader(f, skipinitialspace = True, delimiter=" ")
     # twice as fast as np.genfromtxt(..., names=True)
     hdr = spamreader.next()