Hi Ciaran
It sounds right, I'll do it. The site I'm working on is a bit complex with a number of external extensions to configure. I'm still adjusting details not automatically passed from J3 to J4 due to many custom.css data that I have, fonts, positions, etc.
Nothing that I didn't expect.
Thank you.
Regards
Wallis

Hi Wallis

Thank you for the update.

A good place to start with such issues is to disable all 3rd party modules and plugins. Assuming this resolves the issue, try enabling each one by one until the error reoccurs. This will help you to source the offending plugin/module.

Ciaran

Hi
After many attempts installing, uninstalling and reinstalling the applications and the website itself when I broke it, I ended up getting it and now I have the site in joomla 4 with J51-Emani and the other extensions installed as well. I realized that the problems were all motivated by the extensions that the website uses. I just can't upgrade PHP to version 8 probably due to some extension. I'll try again later.
Compliments
wallis

Hi
Reading other questions/answers I realized that I needed to buy the new version of the template J51_Emani with a discount coupon so I did that.
I tried to install the template and an extension over Joomla 3 and got the following error messages:
Warning: Failed to move file: [TMP]/phpK1wS55 to /j51_emani_j4.zip
Warning: Failed to move file: [TMP]/phposWvk7 to /mod_j51news_j4.zip
Error: Unable to detect manifest file.
Note: I worked on Joomla 3 because I was unable to update to the new joomla 4 before I got rid of the issues reported. I have uninstallad all the conflicting extensions.
Thanks
Wallis