Unfortunately the device is not "field serviceable" (can't flash).
However, that's probably NOT your problem; there are lots of (infrared) devices that learning remotes just can't register and you may have one of them (it isn't an RF remote, right). My suggestions are:
1) try a different learning remote (some people have a couple of old ones); then try teaching the R40 with THAT learning remote (I've done this with an old Marantz).
2) buy/borrow an "off the shelf" pre-programmed remote (if it has your device) and then try teaching the R40 with THAT remote.
Sometimes old/obscure remotes are in a part of the infrared range that doesn't "take".
Thanks for the tips.
I have the remote OneForAll Hamelion, it is perfectly learned with remote Antec. I try teaching the R40 with him, but the result is negative.