diff --git a/dedrm_src/scriptinterface.py b/dedrm_src/scriptinterface.py
index 6154a2a..8cadade 100644
--- a/dedrm_src/scriptinterface.py
+++ b/dedrm_src/scriptinterface.py
@@ -142,6 +142,7 @@ def decryptpdb(infile, outdir, rscpath):
 
 
 def decryptk4mobi(infile, outdir, rscpath):
+    errlog = ''
     rv = 1
     pidnums = []
     pidspath = os.path.join(rscpath,'pidlist.txt')