Try clearing the browser cache (history, data, etc. depending on your browser). We have made some changes in how our login setup works recently and your computer may be trying to load older pages. Wherever you start (www.ptg.org or my.ptg.org), the login screen where you enter your username and password should say my.ptg.org at the top.
Other things to try:
A. Be sure you are logged out of www.ptg.org and my.ptg.org on any other device (phone, other computers, iPad, etc.) or browser. Logout at my.ptg.org first, then login through www.ptg.org. Refresh the page whenever you move back and forth between web sites.
B. Clear your browsing history (empty cache, clear recent history, reset Safari, etc. depending on your browser) and remove cookies. You can usually do this under the Tools (or Safari) menu. You may also need to delete any bookmarks saved for www.ptg.org. Type www.ptg.org into the browser address line.
C. Check your security or privacy settings for your browser to make sure they are turned off, or that you are not blocking all unapproved content.
D. Check the firewall setting on your computer. You may need to turn it down. You can also add trusted sites.
E. Update your browser version.
F. Try a different browser (Firefox, Chrome, Safari). Here is a list of compatibility issues with individual browsers.
G. Login at http://my.ptg.org and see if you are also logged in at www.ptg.org by clicking on PTG Home under the HOME button on the top menu.
H. Restart your computer.
I. If you are trying to login from a computer attached to a network, talk to the network administrator to see if there are firewall or proxy settings that may be causing problems.