High Sierra: Slow boot, no Time capsule!

Hi all!

Little issues here on my Macbook pro running High Sierra!

Basically: I have a late 2010 13" Macbook pro.

I updated a couple of weeks ago from Mavericks.

Since then two major problems:

-1. Slow Startup (even after PRAM & SNC) and also when opening any application (Spinning pinwheel....)

-2. Impossible to "connect" to the time capsule.....

I have Bootcamp because I need to use Windows/Revit.

I had it before when running Mavericks and never had any issue (with OS x), but I repartitioned because of some issues with Windows. Before ripartitioning I thought: might as well try upgrading to lates OS x......hhhmmmm..maybe not a good idea after all...

Anyone's able to help me before I downgrade OS x and......repartition yet again?

Many thanks!!

H.