Applies To:
  • CitectSCADA 7.xx

I have upgraded from V5.5 (or earlier) to V7.0, and cannot connect to Citect via CTAPI. I have tested with the CTAPI tester and receive the error “Run-time error 53. File not found:ctapi.dll” but this file exists in the bin directory. What is the issue?


In V7.0, some of the components have been compiled using a newer version of Visual C++ (Version 2008). You will need the Microsoft Visual C++ 2008 SP1 Redistributable Package (x86) to use the Citect V7.0 CTAPI.


This is available for download from the following location:



 CTAPI, Run-time error 53, ctapi.dll