I asked my webhost to upgrade my server from 7.4 to 8.0.  Immediately the site went down (HTTP 500 error).  They found this in the error located at:  /home/directory/public_html/error_log

[21-Oct-2022 02:15:55 UTC] PHP Fatal error:  Declaration of
IPS\autowelcome_hook_validatehook::postRegistration($noEmailValidationRequired
= false, $doNotDelete = false) must be compatible with
IPS\_Member::postRegistration($noEmailValidationRequired = false,
$doNotDelete = false, $postBeforeRegister = null) in
/home/directory/public_html/init.php(820) : eval()'d code on line 79

[21-Oct-2022 02:15:55 UTC] PHP Fatal error:  Declaration of
IPS\autowelcome_hook_validatehook::postRegistration($noEmailValidationRequired
= false, $doNotDelete = false) must be compatible with
IPS\_Member::postRegistration($noEmailValidationRequired = false,
$doNotDelete = false, $postBeforeRegister = null) in
/home/directory/public_html/init.php(820) : eval()'d code on line 79

[21-Oct-2022 02:15:55 UTC] PHP Fatal error:  Declaration of
IPS\autowelcome_hook_validatehook::postRegistration($noEmailValidationRequired
= false, $doNotDelete = false) must be compatible with
IPS\_Member::postRegistration($noEmailValidationRequired = false,
$doNotDelete = false, $postBeforeRegister = null) in
/home/directory/public_html/init.php(820) : eval()'d code on line 79

How to fix?  Thanks

Your problem looks to be related to the auto welcome hook you have installed. Disable it for not. You might need to disable all 3rd party resources and re-enable them one by one to see which ones cause you problem. 

Work with the resource author for any updates. 

Worked like a charm - thank you!!  

I’m glad it worked for you!  🙂 

Thanks for your help with this one, @Randy Calvert.

You're a wealth of knowledge mate and an asset to Invision Community and its clients. Keep up the great work!