I/O error on NAS storage, only in certain conditions

I have the following:

• QNAP EC12xxx series with 36TB.

The QNAP comes with default folders such as Public, Downloads, Web, Usb etc etc. These cannot be deleted!

In windows I can write to all these shares" with NO problem, either copy and past or drag n drop.

Work Perfectly

The Issue

We are testing a video rendering software. Where it has watch folder, Video In > Process > Video Out.

Now, here is the strange thing I do not understand. If I use the Public Share, everything works.

If I have the VIDEO OUT folder under the share of WEB. I get an error. Saying the program has an I/O error, unable to copy to location xxx.xxx.xxx.xxx./web/video out. However If I copy the file myself, i.e. copy n past or drag n drop. it works.!!!!!!! But if the software tries to output the files DIRECTLY to the WEB share it does not work.

My thoughts

• I have confirmed it is nothing to do with permissions, well to the best of my knowledge but I could be wrong.
• The system works under the share of Public there for it cannot be the software
• The system also works if I create a new share e.g. TEST SHARE.
• So for me, it has something to do with the QNAP system which is based on Linux, however I am not sure what. The fact I can copy n past works perfectly and that the video system cannot export directly to the WEB SHARE is confusing me a little
• I have also tried a TEMP scratch folder. The video is rendered to the LOCAL drive or a network drive and then moved once the job is complete. However this does not work as well.

Thanks