I attached multiples .pdf files to an email. Tried to attach the next file before the previous 1 finished attaching. Got error message "this "**" file cannot be attached until the files already attached are finished uploading". Was never able to attach that 1 file to the email that I received the error message for; was able to attach subsequent files to that same email & send it. Now, I often get the same error message, even if I only attach 1 file & esp. when attaching .ai or .jpeg files. What can I do to fix this problem?