Subscribe 2 not working

Did a complete upgrade (wipe server files and replace) from 2.5.1 to 2.8.2 recently. Deleted and installed new version (4.18) of subscribe2 plugin. This is the same one in use before with the same settings. All the e-mail address were readded. However no e-mails notifications are being sent. The host company tells me it is broken from the upgrade. However the plugin is in the approved list here. Anyone have any ideas on what I can check to fix this?

I was hoping they would get me the web file log as recommened in the plugin site to verify it is not being captured by a spam filter.