Properties on images locking when transferred to PC

[Judgeatc]

Normally, I transfer images from my phone to my lap-top before image-processing them with Photos on Window 10.

Recently (after June update of phone?) I've been having problems when I try to process the copied images, which are coming up with an error, as if the photos are 'property locked'.

The photos process OK in an other programme on my laptop (InPixio), but Photos is slightly easier to use for basic/routine tasks and I'd like to continue using it as my main image-processor for my transferred image files.

Any ideas what is going on?