Sounds like there is one or more validation rule(s) in force for appointments. When you right-click on the calendar folder --> select properties
What value appears in the box beside "When posting to this folder, use"?
If the value shown is not "IPM.Appointment" but rather something like "IPM.Appointment.SomeName" - you are using a custom form for the folder which likely has some validation rule for a field that is not being met. In this case, the options are:
#1 - If you don't want to use a custom form - select <IPM.Appointment>
#2 - If you do need the custom form, you will need to find out what field has validation rules and either correct as required or ensure that whatever it is looking for is entered prior to saving the appointment.
Thanks for the tip. But I checked what you said and the value is set to IPM Appointment. This is a personal computer and I have pop account. Now with that said my previous version (2007) and 2010 are Home Use Versions aquired thourgh the state agency I
work for ( Microsoft Office Professional Plus) if that makes a difference. They were both registered and activated. If you need any further info please let me know. Again Thanks