Ak máš čas, potom skúšaj, hraj sa... Je to síce pre excel, ale podobné to bude pre word...
*** SOLUTION ***
1.- find subkey of file that doesn't open using double click:
1.1- find extension you have conflict in HKEY_CLASSES_ROOT\ (ie: HKEY_CLASSES_ROOT\.xlxs) and then read data of (Default) value (ie: Excel.Sheet.12)
1.2.- find that value again in HKEY_CLASSES_ROOT\ (ie: HKEY_CLASSES_ROOT\Excel.Sheet.12) and look inside subkey shell\open (ie: HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open)
2.- disable DDE through:
2.1- rename original ddeexcec key to ddeexec.bk (ie: original HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\ddeexe c gets named HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\ddeexe c.bk)
WARNING: in next step (2.2) be sure to do not rename command key; command key and command value are not the same things (keys are like folders and values mostly like files inside folders)
2.2- first, look inside comman subkey (ie: HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\comman d), then rename command value to command.bk (ie: HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\comman d\command gets named HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\comman d\command.bk)
3.- be sure correct non DDE command is set as data of (Default) value in command subkey:
3.1 Verify data of (Default) value match this pattern: "...excel.exe" "%1" /e (ie: the value which data was verified is: HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\comman d\(Default))
3. 2 If data verified do not match, then edit it in order to match the pattern. (ie: data of HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\open\comman d\(Default) was setted to: "C:\Program Files\Microsoft Office\Office12\EXCEL.EXE" "%1" /e)