I am being told that my permissions are set to 755 and I keep getting errors. Cannot even update the version of abantecarte as I get these errors:

However, the issue still persists the login completes, but the redirection loops back to the login page instead of proceeding to the account dashboard.

one of such unexpected deleting of session can be 3d-party login extensions.
Try to uninstall them completely if presents.

I would like to help Abantecart development community along with 2 of my programmers that I have hired to support Abantecart for our businesses (as I love Abantecart) and to figure out a good solution in relevance to Extension development and the Market Place.

@Ali Arslan - is One of my programmers currently discussing some technical matters with you in a different thread.

I have pointed out this before as the developers releases new versions of Abantecart, we currently have no mechanism in place to verify what extensions will continue to work, what will need an update from the extension developers and so on not until upgrade is done. On top there is no proper mechanism in place to get the updated version extension version from the extension developer besides re buy the extension all over again? may be I am wrong but this is what I am seeing for extensions I have purchased previously. No upgrade option available.

It appears the extension developers and code developers doesn't have a common discussion group where a co-ordination is happening between developers/Extension developers and where most popular extensions are first updated before the release of the new Abantecart code gets released to the public.

We also need a feature while doing software update where the abantecart notifies admin what extensions will no longer will remain compatible if they upgrade to new release prior to doing the upgrade.

Furthermore, we have dead, and really old extensions still in market place and they need to be removed.

Based on my experience working with few extension developers, the support is not top notch. You get piece part responses and very vague replies when you run into issues.

OUR GOALS

1. How do we establish a proper synergy between extension developers and core code developers?
2. How do we make extension developers accountable to provide proper support?
3. How do we automate extension update process more cleaner for the users.

Above are just suggestions not a criticism towards anyone.

yes, structure is correct.

Do you have some old incompatible extensions installed? Can you try disable them?

please check this sql-request of upgrade script.
https://github.com/abantecart/abantecart-src/blob/1.4.1/public_html/install/abantecart_database_upgrade.sql#L87

Be sure table customer_sessions presents in the database