In which case I believe this is not possible.
I would suggest you get your friend to contact the hosting provider to redeem the login details to either PhpMyAdmin or the cPanel.
Once done, you will need to start recovering the password which can be done via PhpMyAdmin. The following explains this more in detail:
How do you recover or reset your admin password?
You will also need to change your account from an Admin to Super Admin. To do so, follow these instructions.
- Login to the Joomla Admin panel, and get the user ID for the super admin group.
- Go to the
#__users
table in your database and find your user. - Change the
usertype
to Super Administrator - Change the
gid
to the ID of the super admin group you found in the backend.
I believe these is everything you will need, however bare in mind that it has honestly been years since I have ever used Joomla 1.5 so I might have accidentally missed something.
Hope this helps
Note:
##Note: MakeMake sure once you have everything sorted, you update to Joomla 1.5.26