Drupal errors "Notice: Undefined index: profile in..."

Ah the joy of procedural programming in a weakly typed language.

There are two issues here:
1. Drupal is reporting notices
2. Datastructure mismatches

The particular above notice is created when php tries to access a index of an array where the variable is not holding an array. In general this notice will not cause problems with Drupal functionality. You may want to turn off php reporting notices. To do this you can change php's error reporting.

In php.ini use:
error_reporting = E_ALL & ~E_NOTICE

In .htaccess user:
php_value error_reporting 2039