How can I transfer Thunderbird Portable to my computer?

basically it is simply a copy paste procedure, just copy the profile, particularly the mail folders to your installation on the desktop. Start desktop version adn all is here.

You can also copy whole thunderbird to some data area (do not put it to progr folder)and you can use directly this way. Some extensions might need reinstall, but rest should work

Just as a side note, there are some benefits to using portable apps as desktop apps, particularly if you create a second partition, separate from Windows. This way, it's much easier to reinstall Windows should the need arise while keeping all your apps in tact. It's also easier to thoroughly defragment your apps for optimal desktop performance. AND, should the need ever arise, you can very easily copy all your apps to a portable device, and use them on the go (for example you might visit and stay with a relative or friend for a period of time). Once you return home simply resync your portable device with your desktop and it was like you were using your desktop the whole time.

This is one way I use PortableApps. Just something to consider.

Two points I'd like to add...

First, it is much easier to have Thunderbird designated as your default email client instead of trying to force Windows to use ThunderbirdPortable. You'll want the default designation firmly in place to make it easier to have another program (such as your browser) to fire up the correct email client when you click on a mailto link.

Second, if you want to copy and paste your profile from portable to either regular Thunderbird or a hard-drive portable copy, you'll need to start the permanent copy and begin configuring the email client. That way, the right profile folders will be created, and you can have a place to paste the profile into.