Quote from: chenchunyu88 on February 19, 2014, 07:53:42 PM

I have 2 windows 7 desktop running with the same bitcoin wallet.

This is a very bad idea. At best it will lead to confusion. At worst, if you are not very careful, it can lead to losing bitcoins.

Quote from: chenchunyu88 on February 19, 2014, 07:53:42 PM

If it's a hacker, why didn't he/she also steal BTC from other addresses in the same wallet. And why didn't he/she drain my litecoin wallet as well. And the BTC sent has never been spent. It doesn't make any sense.

If it's a hardware+software issue, do you think if there is any way to recover them.

If you are absolutely certain that you never created a transaction to either send:

3.36400639 BTC to 1PbqBj5N1QHszSR244Ubh9KzoJaThM2twi

or

0.00153218 BTC to 1HwNG7uzc2asJSvfKETgu9VBFd9BmxAUb5

then this looks most likely to either be a hacker, virus, or trojan program that you installed that gained access to the private key of the 1HwNG7uzc2asJSvfKETgu9VBFd9BmxAUb5 address.

Is this an address that you imported from somewhere? Have you ever exported the private key of the 1HwNG7uzc2asJSvfKETgu9VBFd9BmxAUb5 address? Do you have any unencrypted backups of the wallet that contains the 1HwNG7uzc2asJSvfKETgu9VBFd9BmxAUb5 address stored anywhere?