Trend Micro and ZIP file corruption

I’m having issues where zip files are coming in and are corrupted. Using winrar to repair them works some of the time, but the majority of times it still has a file in the zip that is corrupted. I called Trend but they say that they can guarntee that it is not their software that does it.

Logic tells me that it must be the trend software, as its set to scan incoming attatchments.

I would turn off scanning for ZIP files, but we had a zip based virus that decimated the company a few years back.

any help would be GREATLY appreciated.