: If a certificate shows as "Invalid" when opened in Explorer, it may be because cryptext.dll is not working correctly or is being blocked by third-party crypto software like CryptoPro or Continent TLS.
| Feature | CryptExtAddCERMachineOnly | CryptExtAddCERHwnd | |-------------------------------|--------------------------------------|---------------------------------------------| | | No | Yes (store selection dialog) | | Target store scope | Forced Local Machine | User chosen (User or Machine) | | Admin rights required | Yes (for write to machine store) | Only if user picks machine store | | Return value | BOOL success/failure | HWND of dialog (or NULL ) | | Primary caller | Automated tools, certmgr (machine) | Explorer .cer open, MMC snap‑in | | Error on duplicate cert | Silent fail (no overwrite) | Dialog warning + user decision | cryptextdll cryptextaddcermachineonlyandhwnd work
Are you trying to , or did you find this command in a system log ? : If a certificate shows as "Invalid" when