VirtueMart installation problem (Joomla!)

If the installation of VirtueMart version 1.1.3 for Joomla! 1.5.10 fails, a manual installation is needed. The error message says that some critical components of VirtueMart are missing. In addition to the following instructions, read the VirtueMart installation manual.

1. Download the VirtueMart Manual Installation package for Joomla! 1.5 from VirtueMart website.
2. Unzip the contents of the archive to a folder.
3. Upload the subfolders and contents using ftp to the web server running Joomla! according to instructions in the VirtueMart installation manual.
4. Use a ftp program or login using a shell to change permissions of the catalog administrator/components/com_virtuemart to 777.
5. Change the permssions of the file administrator/components/com_virtuemart/virtuemart.cfg-dist.php to 666.
6. Go to http://www.yoursite.tld/administrator/index2.php?option=com_virtuemart and perform database installation according to instructions in the VirtueMart installation manual.
7. Follow the VirtueMart installation manual for the rest of the installation process.