[jasperschellekens]

You provide us with very little information.
Which line gives you this error?
This error describes the error quite exactly actually. Try to understand it literally. Function uses both return and return value.
My assumption is that you have this under ondialogresponse:

Код:

return;

return 1;

Changing this to ( most likely 1 but could be 0 depending on the code) return x; (e.g return 1 will probably fix this issue.

If the above does not solve this, my second guess would be that the problem above could be found under the following functions:
SPD
SCM
SCMF