Watched folder stuck on "analysing"

Watched folder stuck on "analysing"

I have a watched folder on an external drive, next to which the yellow "sync" logo appears:

When I click the yellow logo, the following window appears:

However it is stuck on "analysing", I never get to the point where it displays the number of changes.

When right click and "synchronise now", I get a loading bar with some activity in the background, but I never shows the number of tasks.

When I try to quit Peakto, it says that there is an active task in the background, but I have no clue how to see what it is or what is the progress of this task.