My watch-only address is currently being ran on Electrum 3.0.6 with Windows 10 and it appears the zbar reader is not installed for me. When I go and try to load from QR code it says "Cannot start QR scanner; zbar not available".
Did you not see the following note on the Electrum download page?
Note: The QR code scanner is not supported in Windows binaries
Is there a way I can use zbar on windows 10 or do I need to get another bootable USB with an OS that supports it?
zbar is available for download and install, but it doesn't seem to be compatible with Python:
>>> libzbar = ctypes.cdll.LoadLibrary('libzbar-0.dll')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Program Files\Python36\lib\ctypes\__init__.py", line 422, in LoadLibrary
return self._dlltype(name)
File "C:\Program Files\Python36\lib\ctypes\__init__.py", line 344, in __init__
self._handle = _dlopen(self._name, mode)
OSError: [WinError 193] %1 is not a valid Win32 application
...even though you can run zbar just fine from the commandline?!??
Apparently, this is usually indicative of the .dll being compiled for 32bit architecture... and Python being 64bit...
As for your alternative idea... the QR code should load up fine using a QR Code scanner (like webqr.com)... However, the data in the QR Code is stored as a
Base43 encoded string... that is to say, it looks something like:
E:W-P131.RRM+R91DWWMGE0EQRXD:+879DLKFM.S2C9T/XZP:ZV8RV-*/H*X93O44A+1HS-J1F6:D266RS.Z8O9AYSJ*278CCUQ2H4Z6YWM9CTH66YH6MXFSJ3H7-YBASEABDYWOYGW5K.X0CG4QP6BKDUTWE.1B9MBWT68*B4EGKSWPLPQ2N2/8FW1WCC4:J3/:O7$0+N20QGS*OBXE9:RIQ8U/.MYC.75G*S$6DHA*YEVM3/$VRMT3$/1TNN:.XTN1.Z7:1JZWWTQ7$PG7EOZ:T8O-*PMNUOKN0NBT/CT*.JRU69PYTUI3MQK3-VL.4LCUCM2++YS:
Decoding this to raw hex is not exactly a simple task... by stepping through the Electrum Python code (and a bit of trial and error)... It is possible to get this to convert to:
0100000001e90bbe1976e7056eca27ea7a280948c17be71cd6f9936c16d4a7afddcb1ac31f010000006b483045022100c4afaa26eecb143927815969f5b409647d7fcbc24f5456f69f80e0ca631a6fa802200f537578611a9d14fb13e37f962a161c6a24ec5a356d26a0db4659d0fc2b77480121028087725567ce3b2395d019b430d9948dd7a91508a32d69d649cc4c1f67cd50b3ffffffff0218b39d00000000001976a91400a99b3e32116afa227b180c26dd03a0fcd7dce588ac319e0a00000000001976a914bcb55f0e60f9859de8a6467f9fcab69745028bf688ac00000000
Honestly, if you're set on using QR codes, for now you'll most likely need to use another OS.