Updating machine version file
Please note that Word Press 3.7 introduced an easy to use one-button updater which will take you directly to 4.6.1.This update step is safe, and it is possible to one-click update from 3.7 to any later version. All of your Word Press data, such as Users, Posts, Pages, Links, and Categories, are stored in your My SQL database.If you plan on upgrading across more than two major releases, you should consider upgrading incrementally to avoid potential conflicts and minimize the risks of database damage.For example, if you plan on upgrading from 2.5 to 4.6.1, upgrade to 2.7 first, followed by 2.9, then 3.1, and so on. Older versions of Word Press can be downloaded from the release archive.
Please read Backing Up Your Database for a detailed explanation of this process.It is extremely important to back up your database before beginning the upgrade.While the methodology given below is the "safe" approach, as long as you have proper backups, then it is indeed possible to upgrade directly from the very first version of Word Press to the very latest version in one-easy-step.Word Press does support this process, and Word Press is extremely backwards compatible in this respect.
Please continue reading the Detailed Upgrade Instructions.
Remember, if you do encounter problems, re-read the Instructions below to insure you've followed the proper procedures and consult Troubleshooting: Common Installation Problems.