Is it possible to disable plugins via d/b?

I’m not sure if you can disable plugins via the database, but since you have cPanel access, you can temporarily rename wp-content/plugins. Doing so will forcibly disable all plugins and hopefully get you access to the front-end again.

it’s possibly my theme so is it possible to change theme via d/b?

See this for a database solution:

https://www.wpbeginner.com/plugins/how-to-deactivate-all-plugins-when-not-able-to-access-wp-admin/

thank you

Okay, still throwing 500 error, so MUST be my theme? Is it possible to change the theme via the d/b wp-options table? I did search this site first for an answer/topic about it but couldn’t find one =S

Errors like this are logged. Check the error log on your server. If you can’t find the log, please contact your host.

Meantime, enable wp_debug and wp_debug_log and after an error, look at wp-content/debug.log to see if anything gets logged there. https://codex.www.ads-software.com/Debugging_in_WordPress

You can also try this: Please attempt to disable all plugins, and use one of the default (Twenty*) themes. If the problem goes away, enable them one by one to identify the source of your troubles.

Per error_log:

[15-Aug-2017 18:52:09 UTC] PHP Fatal error: Directive ‘allow_call_time_pass_reference’ is no longer available in PHP in Unknown on line 0

Plugins disabled, so probably my theme. I found #124 in wp-options where my theme is listed (Atahualpa) can I just change that to i.e. ‘default’ or ‘twentyeleven’ or whatever and rename my Atahualpa theme folder to something like Z-atahualpa? Or is it more involved than that?

Steve, in reply to your above replay:
How can I change the theme if I can’t access the dashboard??????

also how can I enable wp-debug and do your suggestions if I can’t access site/dashboard?

sorry, yes, I made wp-debug ‘true’ in config file…. looking for debug file now

OK, this is from the error-log: (asterisks to mask my directory)
[27-Jun-2016 21:14:41 UTC] PHP Notice: Undefined index: asdf in /home/******/public_html/index.php on line 16
[27-Jun-2016 21:14:41 UTC] PHP Notice: Undefined index: asdf in /home/******/public_html/index.php on line 20

just looked at the index.php file and line 16:

/** Loads the WordPress Environment and Template */

there is no line 20
=S

PHP Notices are not errors and won’t cause the 500 error. Did you switch the theme to ‘twentyseventeen’?

https://www.inmotionhosting.com/support/edu/wordpress/change-theme-in-db

Thanks for above link, answered what I was asking. but I also changed option for ‘current_theme’ to twentyseventeen as well as the stylesheet and template options. still getting the 500 error, will wait awhile for server crons to ‘catch-up’……….. =S (yes I’ve cleared my cache)