I have made a Paradox program that I have supplied to customers who have 
installed it and used it for many years with no problems. Now suddenly 
it doesn't work.
After the installation, when opening the program, the following error 
message appears:

Unable to find sequence number 515 in DLL file
Program Files (x86)\Corel\Paradox 9
Runtime\Programs\PXRSRV32.dll

The question is why.

Thank you

Bengt