Browser history should show you exactly what wallet provider you used.

There is not currently any BTC in the wallet minus a few hundred satoshis:

https://blockchain.info/address/14V6pKw3AaPcyRpqvff26B2eLdiNRJSz8b

Makes me wonder if they have moved its some kind of exchange or something.

If its not in your history, one final shot is to narrow it down by going to CMD, typing ipconfig /displaydns (DO NOT FLUSH THE CACHE)

It will take a while and probably display hundreds of entries, but it will narrow it down, drastically what site you need to search for, if its still in the DNS cache. Do this ASAP as it is often flushed automatically.

EDIT: I think this is a spam, the wallet hasn't been used for at least two months.