Any list with C5 VFP7 Error and how to solve or obviate it?

I have :

VFP7 SP1 Spanish
Windows XP Prof SP1 Spanish
Visual Source Safe 6.0c


Two C5 are disturb me.

1) When I have a bug showed in the debugger and try to repair (rigth mouse click-repair), sometime I have a C5, other time VFP deletes the VCX and VCT where the class is defined.

2) I program the tabindex in a class form. When I push tab in the last field (txtbox) for go to the first field (txtbox) sometime I get a C5. If I add a new field to the form at last in the tabindex, then this is where I get the error.

Regards,
José Luis.