In order to get rid of this annoying password popup, all we need to do is generate a public/private key using Putty and install your public key in your server. This of course assumes that you are running a SSH on your server and have already setup your SVN repository.
We can generate a private/public key using Putty’s Key Generator, the defaults should suffice, first generate the keys then save the private and public key. The public key will also display on the top square of Putty’s keygen, copy this key in it’s entirety and paste it into your server’s ~/.ssh/authorized_keys2 file.
We can now test this by initializing Putty’s SSH client and configuring it to use the private key we generated. Under ‘Connection > SSH > Auth’ we will see an authentication parameters dialog with a field called ‘Private key file for Authentication’, use the browse button to find your private key file. This tells Putty to use this key to authenticate with the server, under ‘Connection > Data’ enter in your username under ‘Auto-login username’. Go back to ‘Session’ enter in your server address under ‘Host Name’ and save your session with a useful name, think of something more descriptive than ‘mysession’. Click on the Open button you should be automagically logged-in.
Next step is to setup SVN_SSH environment variable, right click on ‘My Computer’ and go to properties, ‘Advanced > Environment Variables’, under ‘System Variables’, click on new and enter SVN_SSH for the variable name and ‘C:\Program Files\TortoiseSVN\bin\TortoisePlink.exe’ for the variable value, make sure the path is correct and using the double back lashes (\).
Now click on your ‘Desktop > TortoiseSVN > Repo-browser’, the URL should look something like this svn+ssh://mysession/path/to/svn/repo. There are a few parts to note here, we are asking for SVN over SSH (svn+ssh), we are using the session name you saved under Putty’s ‘Saved Sessions’ dialog, and the full path to the svn repository.