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Can I upgrade from version 4.1.7 directly to version 4.2.7?
I've gone to the previous versions page and upgraded to 4.1.7
Here is what I'm trying to accomplish.
Version 2.1.7 is running on a 2.5.28 site that I'm upgrading to 3.6.4
I've never had much luck upgrading a 2.5 site directly to 3.6. I'm migrating the data between the 2.5.28 site and a new 3.6.4 site.
I have JomSocial 2.1.7 installed on the Joomla 3.6.4 site. The control panel on the 3.6.4 site is blank but I expect that when I upgrade it will be fine.
Now that I have 2.1.7 on both sites my plan is to move the JomSocial 2.1.7 database from the Joomla 2.5.28 site to the Joomla 3.6.4 site. Once I've moved the database I'll continue the upgrade process on the Joomla 3 site to bring JomSocial to version 4.2.7.
I'll also move the Joomla users and user_usergroup_map tables to match with the Users in the JomSocial tables.
The big things is you need to focus the upgarding Joomla from 2.x to latest version, because that is really tricky one..
Regarding upgrading Jomsocial it wil be very simple, you only need install to the latest version without any issue.. if you have any issue on jomsocial then, please let us know.