Files slow to open in Windows 10

Since I upgraded my PC to Windows 10 (Windows 10 Pro 64 bit), my excel files now take up to 30 sec to open.
Excel.JPG
I get the Excel opening window above which sticks on 0%, remaining visible sometimes for 30 sec, until the file eventually opens.
I have tried a repair install of Office 2010, but that did not cure the problem.
I cannot find what may have changed to instigate this delay.
Any pointers would be most welcome.

Is it an upgrade to W10 or a clean install. If it's an upgrade, that's most likely the problem. I'm running a clean install of W10 on an old clunker & it opens excel files in a second or two. You have to do the upgrade to get it to activate or you end up buying W10.
My advice. Do a clean install as it's always better than an upgrade

Yes, it was an upgrade not a clean install.
I was coming to the conclusion that a reinstall or refresh might be the only cure.
Two curiosities though are first, this behaviour did not happen immediately but began a few days after the upgrade.
Secondly the same delay is evident with one other program (nothing to do with Microsoft Office) and that too began a few days after the upgrade.
Everything else seems to work perfectly.

When I upgraded mine I ended up with a hybrid of W7 & W10, some parts of windows had the new look & some parts old. I had already backed up everything I wanted, so wiped the hard drive with boot n nuke, did the clean install & now all is almost well. I didn't even bother to test it for a few days after seeing the hybrid hotch potch mess I ended up with.
I have noticed excel 2010 now crashes regularly when saving. It "So Far" seems to be related to the printer driver (Canon) the same printer driver that gave no trouble with W7, there is no W10 driver. It's now set on the Canon XPS driver as default & hasn't crashed yet, it still crashed on the MS XPS driver

Hello Philib1 and thank you for the time you have taken to make suggestions.
Since you mentioned printer driver issues, I tried installing whatever HP had for my system which included lots of rubbish I have no need for.
The result was that the issue has now rectified itself (including the other program I mentioned.)
I can't pretend to understand why, but keeping fingers crossed that the problem will not return!

Lets hope it's a permanent fix

Cheers
Phil