Forgive me for reviving a dead thread, but has anyone found a solution to this? I'm getting it every few hours, on the same machine, without closing my browser (Chrome) and without clearing cookies or anything of the sort. It's been happening 5 or 6 times a day for the past couple of months and is starting to get beyond a joke. Between having to wait multiple days for the system to recognise that I've cleared my inbox (and bouncing emails in the process due to my storage being '100% full', even after I've removed half the contents, which proves the system can't math, apparently), having a small storage space to begin with, and this issue, you'd think they'd at least try to correct it.
@minahraven -- due to my storage being '100% full', even after I've removed half the contents
After you delete a message from your "Inbox", it moves to the "Deleted Items" (or "Trash") folder.
Open that latter folder, and remove all its contents.
That will free-up space within your "quota" (1 gigabyte) that Shaw has granted to you.
I am having the same experience on Bell/MTS ( Manitoba ) webmail using safari on a MacBook Pro. Perhaps Shaw and Bell/MTS use same mail program provider. ?????