getting errors when we login to site

Hi,
I'm getting the following errors when I login to the dashboard on one of our client sites. what do these mean?

Notice: has_cap was called with an argument that is deprecated since version 2.0! Usage of user levels by plugins and themes is deprecated. Use roles and capabilities instead. in /home/bnmpro5/public_html/baincil/wp-includes/functions.php on line 3540

Notice: has_cap was called with an argument that is deprecated since version 2.0! Usage of user levels by plugins and themes is deprecated. Use roles and capabilities instead. in /home/bnmpro5/public_html/baincil/wp-includes/functions.php on line 3540

Notice: Undefined index: dashboard_gad in /home/bnmpro5/public_html/baincil/wp-admin/includes/dashboard.php on line 109

    Sohag

    Hi cornelius_butler,

    Thanks for contacting us and we hope that you are having a beautiful day!

    We are also very sorry to know that you are experiencing some inconvenience. Perhaps a plugin conflict test will help us to findout which plugin is generating the notice. Before that please take a backup of your site and database.

    Now to perform the plugin conflict test if you are able to access your site admin then please deactivate all the plugins in the

    Dashboard > Plugins

    And check if the notice is gone. If the notice does not appear after deactivating all your plugins then activate the plugins one by one and check on which one's activation the notice appears. This way we will know which of the plugins is creating the notice.

    If you can not access your wp-admin then could you please access your site via FTP and then go to "wp-content/plugins" folder and then rename all the plugin folders. A helpful practice will be appending string like (-backup) with the plugin name so that while we rename it again we can easily rename it to the original. For example: if the folder name is

    "wp-hummingbird"
    then it can be renamed to "wp-hummingbird-backup"

    After renaming all your plugins please try to visit your wordpress admin panel. If now you can access the admin then rename the plugins to their original name one by one and check on which one's activation the notice appears. Hope in this way we will find out the plugin that is creating the notice. For more about theme/plugin conflict test please visit the following page (You may need to scroll the page down a little)

    https://premium.wpmudev.org/manuals/using-wpmu-dev/getting-support/

    If this does not help to find out the conflicting plugin could you please send us your details through our contact form so we can try to investigate this further,

    https://premium.wpmudev.org/contact/#i-have-a-different-question using the following template:

    Subject: "Attn: Sohag"
    -WordPress admin username
    -WordPress admin password
    -login url
    - credentials (host/username/password)
    -link back to this thread for reference
    -any other relevant urls

    Select "I have a different question" for your topic - this and the subject line ensure that it gets assigned to me

    Please DO NOT post the credentials here as this is a public forum, also would you mind me doing some basic troubleshooting such as temporary deactivating all plugins?

    Please let us know when you do so.

    Cheers,
    Sohag