So, we covered the upgrade yesterday. Yet, far too often,  we run into WHMCS upgrades gone wrong. Something is messy, or something just doesn’t work as expected, or, well, it just doesn’t work like you need. How to fix it? How to revert things? There’s a few things that can be done for WHMCS upgrades gone wrong. If all else fails, hey, please do contact us, and we’ll work with you and see what we can do to help you get straightened out!

Step 1: Identify the problem

What exactly is the problem that you’re seeing? Is it a white screen of death? Then take a look at this post. This might help you solve the problem.
Are you seeing errors on specific modules? Then, you may need to contact the module developer and update their module (assuming they have an update)
Are you seeing template issues? Then, you may need to contact the template developer and update the template (again, assuming they have an update).
Are you seeing expected functionality that’s changed? You may have run into a bug that needs to be reported to whmcs . You did wait until the first stable (ie: 6.3.1) release, right?
Are you seeing include problems? You may just have to re-upload the download again. This happens from time to time, and usually that will solve the problem right away.

Step 2: Resolve the problem

Take a look through the output in step 1. Most problems are going to be covered in there. If you still encounter issues though, please do drop us a line and we’ll see if we can help you out a bit.

Step 3: The backup reversion

This is something that we don’t always recommend. In fact, we don’t recommend doing this at all, unless as a very last resort. However, if you’re working on your public install, you may have to.
Here’s how to do that.

  1. Upload the backup you made to your WHMCS directory
  2. Uncompress your backup
  3. Go into phpmyadmin, click on import
  4. Select the SQL backup you made and import that
  5. Clear your site cache, and all other cache

Voilla, you’ve got an install that’s been reverted to your previous state. If you do this, we do encourage you to contact us , and we will work with you to get the upgrade fixed.