Installation Error Messages; Low Battery; Invalid Signature Or Certificate - Texas Instruments TI-83 Plus Manual Book

Installation Error Messages

Low Battery

Do not attempt to download a Flash application if the low-battery
message appears on the home screen. Low battery indication is
shown on the initial screen. If you receive this error during an
installation, change the batteries before trying again.

Invalid Signature or Certificate

Either this calculator does not have a certificate to run the
application, or electrical interference caused a link to fail. Try to
install the application again.
Error in Xmit
This problem is usually associated with the unit-to-unit cable and
its connection between the calculators. Make sure the cable is
firmly inserted in the link port of each calculator.
TI-83 Plus Solve It! Application Page 17