Today I tried to open an old project. While loading the main DFM form I got a "No mapping for the Unicode character exists in the target multi-byte code page" error.
After wasting some time I figured out what caused it: the form had a custom control that had a property like this: HeaderCellSpacing = 1.300000000000000000.
Meanwhile the control was updated and this property was renamed. This was the reason of the error. It was enough to open the DFM and manually delete that property. After that the form loaded nicely.
Delphi should have been able to see which properties does not exist anymore and automatically remove them. Another proof that Delphi XE7 is totally unworthy for day by day development.
Keywords: No mapping for the Unicode character exists in the target multi-byte code page
