I got an idea which I need an advice on. I was thinking the problem might have arrived due to maybe one or two plugin not compatible with my upgrade.
1. Temporarily renaming the wp-content/plugins folder.(this automatically disables all the plugins).
2. then naming it back to the oringinals - I hope I should be able to log back into the admin if a plugin is causing the problem - meaning I can then be activating the plugins one by one and until I find the "culprit"
My fear is: The site is running perfectly in the front-end, Disabling plugins might hide many things. Should in case the problem isn't solved,
How do restore the activated plugins? without adding to the problem?
Any advice Pls