Export to S3 hangs on ‘Connecting to Amazon’

I bought the S3 extension and have installed the plugins on several sites. All have worked so far except the last one I tried. I am making daily backups to my S3 account and others are updating just fine. When I try to export manually to S3 it goes through ‘Preparing to export’ then ‘creating an archive’ and it just hangs on ‘Connecting to Amazon S3’. I have WooCommerce and WordFence plugins installed on this site. Do you have a solution?