When a Salesperson is trying to start a campaign in the Sales and Success Center and receives the following error:
"An error occurred when trying to create this campaign. Refresh the page and try again"
It might be an indication that a Partner Center admin needs to enable the permission for Salespeople to send a campaign.
To enable this setting; in the Partner Center, go to Administration tab > Customize > Sales and turn on "Salespeople can send campaigns".