using regedit.exe I have manually created a key in registry called HKEY_CURRENT_USER/00_Just_a_Test_Key and created two dword values dword_test_1 and dword_test_2 I am trying to write some values into those two keys using following program import _winreg aReg = _winreg.ConnectRegistry(None,_winreg.HKEY_CURRENT_USER) aKey = _winreg.OpenKey(aReg, r"00_Just_a_Test_Key", 0, _winreg.KEY_WRITE) _winreg.SetValueEx(aKey,"dword_test_1",0, _winreg.REG_DWORD, 0x0edcba98) _winreg.SetValueEx(aKey,"dword_test_2",0, _winreg.REG_DWORD, 0xfedcba98) _winreg.CloseKey(aKey) _winreg.CloseKey(aReg) I can write into the first key, dword_test_1, but when I attempt to write into the second, I get following message Traceback (most recent call last): File "D:/src/registry/question.py", line 7, in <module> _winreg.SetValueEx(aKey,"dword_test_2",0, _winreg.REG_DWORD, 0xfedcba98) ValueError: Could not convert the data to the specified type. How do I write the second value 0xfedcba98, or any value greater than 0x7fffffff as a dword value? Originally I was writing script to switch the "My documents" icon on or off by writing "0xf0500174" to hide or "0xf0400174" to display the icon into [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\CLSID{450D8FBA-AD25-11D0-98A8-0800361B1103}\ShellFolder]