"Roland Perry" wrote in message
...
I've got some Euro locks on external doors, but people keep locking them
and leaving the key on the inside. This means I can't put a key fully in
from the outside to unlock it.

There aren't many locks where you can insert a key from the outside if there
is a key on the inside. The standard locks fitted to patio doors etc will
accept the second key - it feels as if it has gone all the way in - but it
will not turn if there is a key on the other side.

Several times when I've gone out to do the shopping and left my wife working
from home, she has put the key on the inside after I've gone (even though
I've locked the key from the outside and left the inside key out of the
lock), which means I get back and find myself locked out - until I can make
myself heard by knocking/ringing. Now I tend to leave *two* doors with no
key in them, so if the front door is blocked by a key in the lock, there's
always the back door.