Yep, I tried for a number of weeks (many hours of effort), different combinations/rules, but couldn't crack it.

Then I put it away and came back to it a few weeks ago and started fresh and cracked it in less than 10 mins ... I was missing 1 character!

You are a life saver ... this worked ... thanks very much!!!

Are there any steps I need to take, before transferring the coins out to an exchange?

The old laptop is running:
Bitcoin Core v0.15.1
Qt version 5.7.1

Whereas the new laptop is running:
Bitcoin Core v0.21.1
Qt version 5.9.8

Last block time is September 26th 17:59

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?

Thanks for your input/feedback.

After many days/weeks trying to remember/find my password, I stopped trying.

Then a few days ago I started again, trying different combinations/rules using the btcrecover tool and after 1hrs effort, I found the password!!!!  

As you can imagine, I'm very happy.

Now thinking about the timing when to transfer into an exchange (which one?) and coverting to everyday cash ... or just sit on them for them time being.

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.