Why are periods not allowed for s3 buckets

[Tony]

Hi @michael1,
Apologies for the confusion here. Amazon does allow periods in S3 buckets, but then it breaks the certificate validation. Please take a look at this post for more detail:

Unable to Open Amazon S3 Bucket with Windows Client

Hi folks, After a little digging we’ve figured out this issue, at least where bucket names have periods in them. It has to do with Amazon S3’s SSL certificates. They can’t deal with a period in the bucket name, since this is how the URL is referenced and this creates the appearance of an additional subdomain, which can’t be supported by the Amazon S3 wildcard certificate. The best way forward, right now, is to use buckets without any periods in the names.