I recently developed an InfoPath version of my company's performance management tool using info path. To limit access to the form, I added a restricted view page that runs thru form load rules that if you are not the user, manager or supervisor, you are shown this page. Authenticating the employee is easy, a simple rule captures his/her user name when they submit the form. The Manager and Supervisor are pulled from a custom list after they are selected from a drop down as part of our admin data. 

My problem is that depending on where they are logging in from, the username may not match what is pulled from the custom list. Some days it is all lower case (fname.lname) and others it is sentence case (Fname.Lname). 

Any idea why this is happening or a better way to restrict access to the actual Form Library. I need the three to be able to access the form throughout the rating period, but no one elses. Thanks.