MSHFlexGrid CellHeight problem

I've got an MSHFlexGrid (named RtMasterGrid) that is giving me problems. On Form_Load, I fill it with one set of default data. If the user chooses, I empty it and re-fill it with different data. On Form_Load, it works perfectly. When I empty it and re-fill it, the .AddItem works fine and all the data gets added to the grid, but for some reason rows 2 through 8 end up with a .CellHeight of -15, so they don't show on the screen, but they are actually in the grid. I can't change the .CellHeight property if I want to, and the word "CellHeight" appears nowhere in my code, so does anybody know what in the following line of code:

RtMasterGrid.Row = loopctr 'loopctr is an integer loop counter for setting alternating grey-bar

could work fine for row 1, on row 2 reset the .CellHeight to -15, and upon hitting this line of code for row 9 changes the .CellHeight back to 270? I used the debugger & watch window to identify this line of code as the point where the .CellHeight changes.

If I don't empty the grid at all, but simply load the new data onto the end of the first set, I do not have this problem. It only occurs when I empty it and re-fill it.

Thanks in advance,
Alicia (newbie to VB)

This problem is now solved. I had not installed any of the VB service packs at all. I downloaded and installed SP3, and it works just fine now.