In further detail, the problem I'm facing on my MacBook is that I can sign into accounts (or anything that requires a password for that matter, such as Facebook, Twitter, MMORPGs etc.) but I can't sign into them on a PC (Windows computer). The opposite is also true: there are thing I can sign into on a PC, but not on my Mac...
Here's another thing: if I go throught the whole "Forgot Password" process, I can sign into an account on my Mac... but can no longer sign into said account on a PC.
I called Apple Tech support, and the person I spoke with told me to reset my browser, which did nothing to resolve my problem. I tried clearing my browser history, cookies, and cache which still did nothing.
P.S. Has anyone else had this problem? If so, were you able to resolve it, and how so?