Converting your private key will result in a completely different address. Electrum should be able to import any WIF private key.
Well I have a paper wallet with a private key beginning with a 5 (WIF format) but Electrum 2.6.4 seems only to allow to sweep private key beginning with K or L.When I try to enter my privkey beginning with a 5, I cannot click on the "Sweep" button whereas I can click on that button when I put a privkey beginning with K or L.
Doesn't 5 at the beginning mean it's encrypted? I guess you've already figured it out, but next time you could always see different values by inputting them on https://www.bitaddress.org if you have any troubles. I'd suggest downloading the website and doing everything offline for added security.
no, the uncompressed private keys start with 5 like the following (https://en.bitcoin.it/wiki/Private_key):
Code:
5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF
Bitaddress clearly shows that. Here's a screenshot of a test key I generated using it. The WIF key starts with a 5 and the compressed WIF key starts with a K or an L. Counter intuitively the compressed WIF key is one character longer than the other.
