Hi Nikolay, On 5/19/22 10:35, Nikolay Sivov wrote: > + /* vbUseSystemDayOfWeek */ > + GetLocaleInfoW(LOCALE_USER_DEFAULT, LOCALE_RETURN_NUMBER | LOCALE_IFIRSTDAYOFWEEK, (LPWSTR)&first_day, > + sizeof(&first_day) / sizeof(WCHAR)); I think that this should use This->ctx->lcid for locale. Thanks, Jacek