Edit: This seems to be specific to memo fields. If I change the field to varchar(2000) and the column to dbtext it doesn't happen.
It jumps to Variants(710), procedure VarClearDeep(var V: TVarData);
This is all that's shown in the call stack.
VarClearDeep(???)
Other than the above, the call stack is empty. I'm not doing anything with the grid other than populating it, then scrolling left/right. It let's me scroll only so far to the right, then throws the error when a memo column would come into view.
When stepping after the error, this is the call stack.
TWinControl.DefaultHandler((no value)) TCustomForm.DefaultHandler((no value)) TControl.WndProc((134, 0, 0, 0, 0, 0, 0, 0, 0, 0)) TWinControl.WndProc((134, 0, 0, 0, 0, 0, 0, 0, 0, 0)) TCustomForm.WndProc((134, 0, 0, 0, 0, 0, 0, 0, 0, 0)) TFormStdDialog.WndProc((134, 0, 0, 0, 0, 0, 0, 0, 0, 0)) TWinControl.MainWndProc((134, 0, 0, 0, 0, 0, 0, 0, 0, 0)) StdWndProc(269022,134,0,0) StdWndProc(268914,15,0,0) TWinControl.DefaultHandler((no value)) TWinControl.WMSysCommand((274, 61558, 53019577, 953, 953, 809, 0)) TControl.WndProc((274, 61558, 53019577, 0, 61558, 0, 953, 809, 0, 0)) TWinControl.WndProc((274, 61558, 53019577, 0, 61558, 0, 953, 809, 0, 0)) TWinControl.MainWndProc((274, 61558, 53019577, 0, 61558, 0, 953, 809, 0, 0)) StdWndProc(268914,274,61558,53019577) TWinControl.DefaultHandler((no value)) TControl.WMNCLButtonDown((161, 6, 953, 809, 0)) TControl.WndProc((161, 6, 53019577, 0, 6, 0, 953, 809, 0, 0)) TWinControl.WndProc((161, 6, 53019577, 0, 6, 0, 953, 809, 0, 0)) TWinControl.MainWndProc((161, 6, 53019577, 0, 6, 0, 953, 809, 0, 0)) StdWndProc(268914,161,6,53019577) TApplication.ProcessMessage((268914, 161, 6, 53019577, 63654046, (953, 809))) TApplication.HandleMessage TCustomForm.ShowModal ShowCustomerCallDlg(#0#$B#0#0#$D'Ý',$35CCF48) TFormViewForfeitPreview.BtnLogCallClick($35C3C54) TControl.Click TButton.Click TMenuBtn.Click TButton.CNCommand((48401, 6844, 0, 268988, 0)) TControl.WndProc((48401, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TWinControl.WndProc((48401, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TButtonControl.WndProc((48401, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TMenuBtn.WndProc((48401, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TControl.Perform(48401,6844,268988) DoControlMsg(268988,(no value)) TWinControl.WMCommand((273, 6844, 0, 268988, 0)) TControl.WndProc((273, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TWinControl.WndProc((273, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) TWinControl.MainWndProc((273, 6844, 268988, 0, 6844, 0, 6844, 4, 0, 0)) StdWndProc(269000,273,6844,268988) TWinControl.DefaultHandler((no value)) TControl.WMLButtonUp((514, 0, 89, 20, (89, 20), 0)) TControl.WndProc((514, 0, 1310809, 0, 0, 0, 89, 20, 0, 0)) TWinControl.WndProc((514, 0, 1310809, 0, 0, 0, 89, 20, 0, 0)) TButtonControl.WndProc((514, 0, 1310809, 0, 0, 0, 89, 20, 0, 0)) TMenuBtn.WndProc((514, 0, 1310809, 0, 0, 0, 89, 20, 0, 0)) TWinControl.MainWndProc((514, 0, 1310809, 0, 0, 0, 89, 20, 0, 0)) StdWndProc(268988,514,0,1310809) TApplication.ProcessMessage((268988, 514, 0, 1310809, 63652015, (1169, 469))) TApplication.HandleMessage TApplication.Run MyApp