Our experience with Elnec programmers and the Elnec software is that in almost all cases it works first go. However, in a few rare cases, problems do occur. Problems may be caused by a faulty parallel port or by a software conflict (two or more applications trying to use the same parallel port). 

Here is a list of things to check.

• Check that you have selected the correct device. Note that devices with similar part numbers may have different programming algorithms (for example, flash memories from different manufacturers).
  

• Try another PC.

• Check for other applications that may be accessing your parallel port. Be specially suspicious of applications that have a parallel port security 'dongle'.

• Re-start your PC in "Safe Mode". This will run Windows with only essential drivers.

• Use only the supplied parallel port cable. Extending the length of the cable may cause problems.

• Check the Application Notes on the Elnec web site.