I can use SportsTrak to open my old data but newer data sent to me by my interschool organiser gives the error
“File daydtail.tps could not be opened. Error Invalid record declaration (47)”

Firstly download and install the latest version of SportsTrak2100.

http://www.carobcom.com/dlsportstrak2100.htm

To convert your old data, download the stconvert.exe program and documentation from this link.

http://www.carobcom.com/dlstconvert.htm

Run the latest version of SportsTrak you just downloaded. Set the data path to the data you wish to work with. If SportsTrak crashes on any file, then  follow the instructions and use the stconvert.exe program to convert that data to be compatible with the latest version of sportstrak