http://bugs.winehq.org/show_bug.cgi?id=10349
--- Comment #22 from Dmitry Timoshkov dmitry@baikal.ru --- Created attachment 79458 --> http://bugs.winehq.org/attachment.cgi?id=79458 patch
Many thanks for the test case!
According to https://learn.microsoft.com/en-us/windows/win32/dataxchg/wm-dde-ack WM_DDE_INITIATE message should be handled differently from what currently Wine implements. Does the attached patch help?