Dear all,

I have a table which's first field is Date. I use a grid to contain this table in a form(named form2). Recently I got the following error message.
"INDEX internal consistency error", then after I clicked the HELP, it will show:
"internal consistency error (Error 1462)
Internal product error. Visual FoxPro closes all open files and exits.

· Visual FoxPro cannot reconcile two opposing internal states in the product.

Record your recent actions while using Visual FoxPro and then call Microsoft Support."
The Visual Foxpro will close.
I have a button in my form.
The click event is:

select table1
thisform.grid1.ReadOnly=.f.
append blank
thisform.thirdgrid.setfocus()

After clicking this button, the focus will be on the field of Date. When I use the arrow key to scroll up to the first data, whenever I scroll up again, it will output the above error. And if I entered an empty date and scroll down, the error will happen too.

I have 3 indexings before the form is shown. One of them is as below, the other 2 are similar.

select table1
=cursorsetprop("buffering",3,"table1")
index on price to price2
=cursorsetprop("buffering",5,"table1")
locate for code=thisformset.form1.inputcode.value and code2=thisformset.form1.inputcode2.value
thisformset.form2.show

Anyone can help me about this complicated problem?