Website upgrade is a common practice. Keeping up with the latest version of your content management system or website software is a good security measure as it ensures you are dealing with latest security bugs and keeping up with the latest features. But sometimes you decide to upgrade your version of Joomla, and then after the upgrade is done, your website becomes completely unusable or some of its features become broken. Why does that happen, and how to revert back to a previous version of Joomla to undo the upgrade. That will be the focus of this post which essentially will take us the process of reverting back to a previous version of Joomla after you have had some issues with functionality following an upgrade.

Why a Joomla upgrade might break your website

There are several reasons that are behind this, and they mainly are:
1. You have modified the core of your Joomla website: Many website owners modify the core of their Joomla website (or have it modified) in order to add some custom functionality. While this can be necessary, it should be avoided when possible. Only modify the core of your Joomla website when there is no other alternative. Note that in most cases there is an alternative! 99% of the very complicated work on a Joomla website can be done using extensions. You will rarely find any need to modify the core. And, in the very rare cases whereyou have to, it will be good to make changes compatible with future upgrades.
2. You have installed an extension that is not compatible with your current version of Joomla: When you do an upgrade, sometimes a 3rd party extensions can be incompatible with your current version of Joomla, and if this extension is a System plugin that runs on every page, then most likely your page will either show a blank page or will display a fatal error (at best your page will display a warning). There are also cases where an existing extension is not compatible with an upgraded version and it creates problems. So before an upgrade, it is a good idea to check the eyensions to be sure they are compatible with the version you are planning to upgrade to.
3. You have uploaded the files to the wrong place: A Joomla upgrade usually consists of uploading specific files to specific directories. Sometimes the upgrade can consist of just uploading a couple of files to a couple of directories. What if, for example, you need (as part of the upgrade) to upload index.php to the administrator directory, and instead of uploading that file to the administrator directory, you uploaded it to the root directory of your website. Not a single page on your website will work (the index.php file that is located directly in the root directory of your website is used on every page on the frontend of your Joomla website). You will, in such cases, simply locate the newly uploaded file and delete it or simply move it to the proper directory using your file manager.
4. You haven’t finished uploading the files, but you thought you did: As stated above, a Joomla upgrade consists of uploading several files. What if the upgrade consisted of uploading 5 files and you uploaded only 4, and what if the file that you missed is used by those other files? At worst, all of your website will stop working and at best, some of your functionality on your website will be broken. This creates corrupt files on yyour server and will need a complete re-upload or you find a way to resume upload and complete it.

How do you revert back to a previous version of Joomla

Once you notice that the upgrade has broken your website, you realize it is big trouble and have to think of a way out.

Read full post on the Todhost Blog: https://www.todhost.com/knowledgebase/812/How-to-Revert-Back-to-a-Previous-Version-of-Joomla.html

i hope dis will resolved my problem

Pls i need help after updating my joomla site without backup now am trying to login to my dashboard but is showing blankpage but i can access the site but cant login as admin

Prospecmarley:
Pls i need help after updating my
joomla site without backup now
am trying to login to my
dashboard but is showing
blankpage but i can access the
site but cant login as admin

We have dealt with this problem in another article: https://www.todhost.com/blog/how-to-fix-the-joomla-white-screen-of-death.html

Let us know if you have some challenges fiing this. This is usually caused by incompatible plugins when an upgrade is made.