diff --git a/src/quotedprintable.cpp b/src/quotedprintable.cpp
index 81af8e3..dddd180 100644
--- a/src/quotedprintable.cpp
+++ b/src/quotedprintable.cpp
@@ -56,7 +56,8 @@ QByteArray& QuotedPrintable::decode(const QString &input)
     {
         if (input.at(i).toLatin1() == '=')
         {
-            output->append((hexVal[input.at(++i).toLatin1() - '0'] << 4) + hexVal[input.at(++i).toLatin1() - '0']);
+            output->append((hexVal[input.at(i + 1).toLatin1() - '0'] << 4) + hexVal[input.at(i + 2).toLatin1() - '0']);
+            i += 2;
         }
         else
         {