Applies To:
  • CitectSCADA 5.50
  • CitectHMI 5.50

I've installed CitectSCADA 5.50 on my Windows 98 computer and I keep getting Software Protection Failure (SPF) on startup, just after displaying "Initialising Subsystems". I've downloaded the latest driver for my Sentinel Protection key, and I've checked my key using the key update utility and it seems to work ok. What's going on? 

This problem has been introduced because the default value for the INI parameter


has been changed to 1 in CitectSCADA 5.50.

This alleviates a problem seen in KB article Q3570 for Windows 2000/XP computers, but on a Windows 98 machine the cryptographic key needs to be created in the local machine area. If this INI parameter is set to 1 this will not happen. Setting


should allow Citect to start normally.

This problem has also been reported on the Citect Internet Display / Manager Client (IDC / IMC).  In this case it was resolved by adding the above parameter to the IDC / IMC client file (located in the IDC / IMC "Bin" directory). 

Citect has confirmed this to be a problem in CitectHMI/SCADA version 5.50 or later. We are researching this problem and will post new information here as it becomes available.

See also KB articles Q3570, Q3828


SPF, cryptographic key, initialising subsystems