Is your forum behind a Content Delivery Network such as CloudFlare? If so, have you cleared all of the expired assets from after you've upgraded? What does a hard refresh (Ctrl F5) show after attempting to login? What browser are you using? If Safari they no longer follow web standards, so it is not recommended to depend on it.

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
Do you need Forum Install or Upgrade Services?
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