blown_dry when I was on vacation(and at home) and had spotty internet, I found that I didn't always get a completion response from my posts. Through trial and error, I realized that the posts were successful, but just the completion message didn't get back to me, or didn't get sent in a timely manner. Instead of re-posting the same material, I checked the forum from a different tab, and found the post(s) was(were) successful. I might guess that the upload was taking longer than the forum expected, and thus the user gets "unexpected error that something went wrong". Thoughts that come to mind is the server is not responding in the expected time allotted for the platform or the message is getting lost in the bad internet connection.
