"Unable to exit design mode" Error In Excel? - CX-Server Lite version 1.1/OPC version 1.1
When using Excel, somtimes Excel will report that it can't exit design mode because it can't create an ActiveX control that it needs. This may be one of the CX-Server LITE/OPC graphical controls, or even a third party control.
The only workaround to this problem is to use Ctrl-A to select everything on your sheet, create a new excel sheet and then paste your controls onto this new sheet.
Note: if you have any VB code behind the sheet you will need to copy this aswell.
CX-Server Lite 1.0 and CX-Server/OPC 1.1