To reset your Citrix Receiver, just follow these steps:

Down by your time, right-click the Citrix icon.  Sometimes you may have to click the up arrow to reveal it.

On the pop-up menu click Advanced Preferences

Next click Reset Receiver on the new window

Now go back to your Citrix icon and double click it this time

On the Add Account line type

Then click Add

Put in your Citrix login credentials, usually first initial + last name or Student ID number, and Park password

Re-enter your credentials again, this time checking the Remember my Password box

This now resets your Citrix Receiver, many times resolving issues you may have in opening Citrix Windows & Apps.