Unconfirmed transaction since 2 days 2 days ago I've send some btc from my Bitcoin wallet called Bitcoin-QT(Version v0.8.6) to my Kraken account.
But it is still unconfirmed and still don't see anything on Kraken too.

Last week I did exactly the same thing(send my same Kraken adresse), and I received my coins a half day later on my Kraken account.. 

So what can be wrong here? Maybe because of the old BTC wallet version?
I'm feeling a little stressed now..

Thanks in advance.

Grtz,

A BTC Noob
Most likely the fee was very low and it is therefore not being selected by miners for a block. Bitcoin-Qt 0.8.6 is from Dec 2013 and you should consider upgrading to a newer version of the software. The recent versions have vastly improved fee estimation.

You should probably try to doublespend the transaction with a bigger fee. You can find more information and detailed instructions on Why is my transaction not getting confirmed and what can I do about it?.