>I had a quick look at the docs on this but couldn't find any confirmation that redirecting stderror to NULL was a valid option (although I would expect it to be)
>Are you saying that NULL *is* a valid option but would not solve your problem ?

2>NUL is what WinZip support recommends to resolve the issue, but for those who have a problem with the Zip hanging when being executed at the command prompt. As for me, at the command prompt, I was never able to simulate the problem. 1>NUL would redirect for the output, 2>NUL would redirect for the errors. WinZip support acknowledges the problem when the same is being executed from inside an application and we need to achieve a similar approach. The code I released is one that works.