I called Sage and I, too got confirmation that they are aware of the problem (i.e., 403 error) which is apparently only affecting certain logons. Although a fix is currently being worked on to fix ALL logons (I don't know if they have an ETA), they can fix individual logons as requested (which I was told takes about 10-15 minutes per logon). They're fixing mine so if you need yours fixed, call Sage Portal Support at the applicable # below (courtesy of @WayneSchulz from last year).
Once you put the fix request in, log out of the Portal (although I'm not sure if that really matters while they're fixing it but it can't hurt).
They said they'd shoot me an e-mail once it's fixed, at which time you need to:
1.log out of the Portal
2.clear your browser history and temp files
3.close your browser
4.re-open your browser
5.clear your browser history and temp files again just in case
6.log into the portal, and it should now work
Fyi, my issue began yesterday when I couldn't get into certain things (e.g., the Sage 100 Support page); was getting the 403 error. The Knowledgebase seemed to be working okay though. And then at some point today I couldn't even get to certain pages (e.g., Product Resources); was getting that 500 Internal Server error. This 500 error can be resolved by following the bulleted steps above, but it doesn't resolve the 403 error.
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Sage Customer Portal Contact #'s
Posted: 05 Jul 2012 04:24 AM PDT
Sage North America Customer Portal (aka Atlas) Accounts
If customers are having issues getting access to their portal accounts or need login information they can either call the number below (varies by product line) or email
customer.portal@sage.com. They will need their Sage account number.
Sage 100 ERP (MAS 90 and 200) Contact Numbers
Customer Support 800-865-3611
Sales 866-530-7243
Customer Portal 800-865-3611, option 4
Sage 300 ERP (Accpac) Contact Numbers
Customer Support 800-253-1372
Sales 800-945-8007
Customer Portal 800-253-1372, option 3
Sage 500 ERP (MAS 500) Contact Numbers
Customer Support 800-944-5481, option 2
Sales 800-944-5481, option 1
Customer Portal 800-944-5481, option 2 then option 4
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