Generally these kinds of problems are related to the PC the student or staff member is using, rather than anything related to a specific student record or payment transaction. Please try the following self-help troubleshooting tips:
If yes, then try accessing SIS through Firefox and see if that helps.
1. Verify that the user is using Internet Explorer v.6 or v.7, to eliminate the browser as the source of the problem.
If no, then have try Internet Explorer and see if that helps.
2. Have the user try accessing SIS through another computer, to eliminate the PC as the source of the problem.
3. If the user has any extra toolbars or other installed programs that start upon PC boot up (Google Toolbar, Yahoo Toolbar, Weather Bug, etc.) those should be removed using the Windows Add/Delete Software functionality - not just turned off at the View menu, to eliminate them as the source of the problem.
4. Have the user try clearing his/her browser cache and reboot the machine.