From cd49839bc0375bf66882d6d77834f6e6986549fb Mon Sep 17 00:00:00 2001
From: SomberNight <somber.night@protonmail.com>
Date: Thu, 7 Nov 2019 07:07:02 +0100
Subject: [PATCH] transaction: helpful error msg if user tries to load old
 partial tx

---
 electrum/transaction.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/electrum/transaction.py b/electrum/transaction.py
index 5ca5e0611..e010efac1 100644
--- a/electrum/transaction.py
+++ b/electrum/transaction.py
@@ -913,7 +913,10 @@ def tx_from_any(raw: Union[str, bytes]) -> Union['PartialTransaction', 'Transact
     try:
         return PartialTransaction.from_raw_psbt(raw)
     except BadHeaderMagic:
-        pass
+        if raw[:10] == b'EPTF\xff'.hex():
+            raise Exception("Partial transactions generated with old Electrum versions "
+                            "(< 4.0) are no longer supported. Please upgrade Electrum on "
+                            "the other machine where this transaction was created.")
     tx = Transaction(raw)
     tx.deserialize()
     return tx