lost admin toolbar and stock file I am a total Drupal newbie so need advice.

I installed a new module commerce_shipping_postal_code_weight-7.x-1.x-dev, and tried to activate it. I was then advised a couple of other modules needed authorising. I authorised everything and then returned to my home screen.
My left hand column had disappeared which contained my login box, my stock file has disappeared, and so has my admin toolbar.
Logging in using /?q=user doesn't reveal the toolbar, but I am logged in.
I've restored all my files from 24 hours ago with no joy and now am waiting for our ISP to send me a backup database.
The only error message I get is :-

    Notice: Undefined index: search_api_views_fulltext in
 views_handler_filter-&gt;accept_exposed_input() (line 1273 of
 /homepages/11/d95668464/htdocs/drupaltest/profiles/commerce_kickstart/modules/contrib/views/handlers/views_handler_filter.inc).
 Notice: Undefined index: table in
 entity_views_plugin_row_entity_view-&gt;init() (line 20 of
 /homepages/11/d95668464/htdocs/drupaltest/profiles/commerce_kickstart/modules/contrib/entity/views/plugins/entity_views_plugin_row_entity_view.inc).


I had only downloaded and enabled the modules, and they had not been used so I have no idea of how I could have prevented it.
The fault turned out to be that a lot of modules had become de-selected. A good procedure would probably be to print off a module list with all the selected ones shown, this could then easily be checked by future webmasters.