Trouble with tags

Recent testing on a miltusite install with just domain mapping plugin network activated.

The domain.tld/tags/ and domain.tld/tag/anytag are getting 302 redirects to domain.tld

Any body reporting any tag issues with wp 4.5.3?

Is there any htaccess lines to check?
Any wp-config lines to check?

Funny thing is that categories and permalinks to posts all seem to be working fine. i can see tags in admin, add, delete etc. but no tag related url gets anything accept 302 errors.

thanks.