cannot upgrade 1.1.21 to 2.0.10

[aswuser]

I start upgrade file and after a few minutes get message Error!
Unknown Error!

phperrorlog says
Undefined index: database_error in ..../Sources/Subs-Db-mysql.php on line 594
PHP Fatal error:  Call to undefined function allowedTo() in /Sources/Subs-Db-mysql.php on line 595

If I try to run repair settings, I get the same errors -  Undefined index: database_error, PHP Fatal error:  Call to undefined function allowedTo() .

I am running php 5.3

I have searched the forums to try and find an answer but I am at a loss here in what to try next.

Any ideas?

Thanks

[Sir Osis of Liver]

Upgrade php to 5.6, run upgrade.php, then upgrade php to 7.1.

[aswuser]

I already tried that. With php5.6, I get error these errors when I run repair settings:

PHP Deprecated:  preg_replace(): The /e modifier is deprecated, use preg_replace_callback instead in =/Sources/Load.php(225) : runtime-created function on line 3

[Kindred]

Get a new copy of repair_settings.php