uploading item(s) to folder what does this mean

I have just switched to eM Client and a little confused with my Hotmail accounts.

When starting eM Client it states at the bottom Uploading item(s) to folder:

What does this actually mean, where is it uploading to?

It seems to sit with the spinning icon for a long time but there are no errors being shown.

Hi Tony,
when this happens, could you please take a screenshot of this and also go to Tools > Operations > Log tab and copy the content of it here so I can see what operations are being executed?