I have wrote it before, but I still get many business partners contacting me complaining that a test code does not work.

If you want to use a test code with an InterForm400 version, that is earlier than version 2009M10, then you need to install an InterForm400 PTF:

2007M01-2007M09:        PTF 3493
2008M01-2008M20:        PTF 3666
2008M501-2008M526:    PTF 3793
2009M01-2009M09:        PTF 3791

These PTFs are available from our download server http://download.interform400.com/

Please note, that we are no longer able to create either PTFs not test codes for 2004 and 2006 versions, so customers running either of these versions should upgrade ASAP. The 2010 versions does not need any license code PTFs.