I have an old laptop which contains a wallet with 10 BTC.

I’ve purchased a new laptop, installed Bitcoin qt and copied across the wallet.dat file.

After waiting many hours , I’ve synchronized with the blockchain, but wallet balance shown is 0.

Any ideas?

[Background]

Hi,

Can someone confirm if the method of password encryption used in Bitcoin Core / Qt changed, which would prevent me from opening a wallet.dat file?

Background
- In early 2011, a friend introduced me to Bitcoin and got me to setup a wallet and then transferred 10 coins into it.
- Until recently I thought I had lost the file, but by chance a few days ago, I found it on an old USB stick.
- I then installed the Bitcoin Core / Qt software that was on the USB stick and copied the wallet.dat file into the folder
- over the last couple of weeks (using an old laptop), it has synched and confirmed that there are 10 bitcoins in there ... wow ... yippeee !

BUT ... when I try and access the wallet, I'm told my password is incorrect.

I've tried numerous passwords and combinations that I frequently use, but alas I cannot access/transfer the coins.

The friend that originally gave me the coins, said that his brother had experienced a similar problem and resolved it by using a previous/older version of the software.

Is there any truth to this and something I should try and if so, which versions should I target?

Currently the software in use is Bitcoin Core version v0.15.1 (64-bit) & Qt 5.71

Thanks in advance for your input/feedback.