Draw a rectangle on W10

[Target]

It's likely me cos I'm not a regular user, but I'm not able to change the colour of a rectangle, specifically the border

I'm trying to highlight a bunch of fields on a screenshot and can only get a black rectangle (not yellow like I specified).

Any suggestions?

[mouser]

try changing the blend mode

[Target]

try changing the blend mode

thanks mouser! 

For some reason it was set to multiply.  No idea why it was like that, but as an occasional user (and a non graphics person) I don't know what most of these settings do