This is unusual -- we've got lots of users running on Windows platforms without these sorts of problems. You'll have to do some digging around in the login process to see what's happening. Does the OJSSID cookie path and URL match your server's path and URL? Have you tried deleting all OJSSID cookies and logging in again?
Also, have you checked your PHP error log to see if anything has shown up there?
Public Knowledge Project Team
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