mithra62

This isn’t my product, I do Backup Pro, but it could be your region selection.

Basically, depending on what Region you select in Amazon S3 settings, you have different rules for how you can format your buckets. For example, some regions allow dots in names, but not underscores, but another region will allow anything.

So, check that in your settings, if it’s possible in that plugin (again, NOT mine), and that could be your issue.

Forgot to mention this is with Mailpress 5.0

Yeah, I do that too, but it’s a hassle and breaks the writing flow. When you click Preview the post should be previewed without having to take any extra steps.