Preparing the vBulletin Files for Upload 
After you have successfully downloaded the vBulletin package to your computer you will need to prepare the scripts to be uploaded to your web server. We’ve included the instructions for both Windows 7® and Mac OS X® below.

Windows 7®

The first thing to do is to decompress the package into its constituent files. If you’ve downloaded the .zip package and your computer is running a recent operating system, you should have all the tools you need to do this.

To extract the files from the package, open the folder on your computer where you saved the vBulletin package and right-click on its icon. Choose Extract All... from the pop-up menu.


This will open a wizard to guide you through the unzipping progress. Accept the default options and the system will decompress the files from the zip package.

Mac OS X®

The first thing to do is to decompress the package into its constituent files. If you’ve downloaded the .zip package and your computer is running a recent operating system, you should have all the tools you need to do this.

To extract the files from the package, open the folder on your computer where you saved the vBulletin package and right-click (or control-click) on its icon. Choose Open from the pop-up menu.

This will extract all of the files from the package to the current folder.

After Decompressing the Files

When the unzipping progress is complete, you will find that the process has created a new folder called upload and another called do_not_upload.
Note:
As you already have a vBulletin installation running on your web server, you should delete the install.php file in the /core/install directory before you proceed to upload the files.
Glenn Carr 22nd Dec 2007, 01:17pm
Regarding this statement:
"Note:
As you already have a vBulletin installation running on your web server, you should delete the install.php file in the install directory before you proceed to upload the files."

It is unclear to me whether this refers to the install.php in the current installation or in the upgrade package.

[Editor's Note: It is referring to install.php in the newly downloaded files or upgrade package.]
Martin Leonard 04th May 2008, 11:29pm
The install.php should be removed after installation, so you should not have one in the current installation!
unfv 05th Nov 2008, 10:31am
Remember to delete the favicon.ico file from the installation files if you have a custome one on your web site, and if you use vBulletin on the root
Vahid Mafi 24th Apr 2012, 01:32pm
Remember to check your database via phpMyAdmin to see if your database, all tables, and all fields have the same collation.

When vBulletin creates a new table in the upgrade process, it asks MySQL what the default collation for the database is and then uses that. Most MySQL installations default to latin1_swedish_ci (in my case it was utf8_persian_ci). If you have changed collations for any reason on tables in the past then you should change the database to use that as the default to prevent issues in upgrade process.
IggyP 21st Sep 2013, 04:03pm
it should be noted that makeconfig.php also needs deletion
Marc Sacco 24th Dec 2015, 11:18am
Since the potential exploit was discovered, should we delete the entire install directory or still just install.php?

As per vBulletin:

"Tue 27th Aug '13, 12:23pm

A potential exploit vector has been found in the vBulletin 4.1+ and 5+ installation directories. Our developers are investigating this issue at this time. If deemed necessary we will release the necessary patches. In order to prevent this issue on your vBulletin sites, it is recommended that you delete the install directory for your installation. The directories that should be deleted are:

4.X - /install/
5.X - /core/install

After deleting these directories your sites can not be affected by the issues that we’re currently investigating.

vBulletin 3.X and pre-4.1 would not be affected by these issues. However if you want the best security precautions, you can delete your install directory as well. "
Trevor Hannant 24th Dec 2015, 11:20am
As these are the instructions for preparing the files for upload prior to an upgrade, no you don't want to delete the install directory as you then have none of the upgrade files...
Jon Mutiger 14th Apr 2016, 03:09am
The install.php file is now buried a bit deeper in the core directory, the guide should reflect this