The EUDCCodeRange key in the following Registry path contains entries that define the EUDC code ranges per code page.
HKEY_LOCAL_MACHINE\
System\CurrentControlSet\Control\NLS\CodePage\EUDCCodeRange
CodePage REG_SZ FromTo{,FromTo}
Specifies an EUDC code range or ranges.
The value of CodePage is either 932 (Japan), 936 (Simplified Chinese), 949 (Unified Hangeul), or 950 (Traditional Chinese).
The FromTo must be a pair of four digit hexadecimal values separated by a hypen (-). To specify more than 2 code ranges, a comma (,) is a delimiter of each of the FromTo. Any EUDC-related functions do not work without this entry.
For example:
HKEY_LOCAL_MACHINE\
System\CurrentControlSet\Control\NLS\CodePage\EUDCCodeRange
932=F040-F9FC
950=FA40-FEFE,8E40-A0FE,8140-8DFE,C6A1-C8FE