[tbirnseth]

I am trying to upgrade a dev site to 4.3.4 and have to upgrade to 4.3.1 first. However, this includes all the aforementioned issues in the upgrade process which leads to a blank page. Now the admin panel only has white pages. Not sure what to do now.

You don't say whether you followed the two basic issues in the upgrades.

First is commenting out the backup actions in 4.3.1, 4.3.2 and then changing 'zip' to '' to prevent compression in 4.3.3, 4.3.3 SP1 and 4.3.4.

 

Doing those (for each upgrade) should get you there.  First thing I'd do is restore back to where you started from.  Then apply the above patches to those upgrades as you go forward.

[eComLabs]

I am trying to upgrade a dev site to 4.3.4 and have to upgrade to 4.3.1 first. However, this includes all the aforementioned issues in the upgrade process which leads to a blank page. Now the admin panel only has white pages. Not sure what to do now.

 

Try to replace

ini_set('display_errors', 0);

with

ini_set('display_errors', 1);
define('DEVELOPMENT', true);

in the config.local.php file