Why I can not upload files to my form?

I recieve a message saying that your servers are refusing to connect when I try to open files attached to a completed form. 

I did some tests and I didn't encounter any issues. Could you please provide us with a screenshot if you experiencing this issue, so we can investigate?

Thank you.

Thank you for reporting that issue and we are sorry for the inconvenience this may caused you. The issue should be fixed now. We would appreciate it if you could also test it on your side and let us know the result.

I did in the last email. Image below.
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Fixed! Thank you.
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Thank you for letting us know. We are glad to hear that everything works fine now. If you have any question or issues, please do not hesitate contacting us. We will be glad to assist you.