diff --git a/dissect/fat/fat.py b/dissect/fat/fat.py
index 29bd9d6..b2206d8 100644
--- a/dissect/fat/fat.py
+++ b/dissect/fat/fat.py
@@ -40,6 +40,7 @@ def __init__(self, fh, encoding="ibm437"):
         self.fh = fh
         self.encoding = encoding
 
+        fh.seek(0)
         sector = fh.read(512)
         bpb_size = len(c_fat.Bpb)
         self.bpb = c_fat.Bpb(sector[:bpb_size])