Thanks for the info. While there is probably something wrong with the OS (Windows in this case), is there a lighter way in Caché to execute a routine in a separate task ? I am thinking something like starting a new thread or using a thread pool. Does such thing exists ?

Thanks for clarification about the name. I found it was called like that before I saw your post and edited OP.

You are right. There is actually two ways the program send requests : either by submitting form (which result in fields being added to the body of the request as expected). And another way for server side  validation, using a XMLHttpRequest. It append everything to the URI. I might fix that part.