Stack mode greyed out

[jean paulg60780484]

I am trying to use Stack mode however it is greyed out. Can someone help?

Photoshop CC 2017

Thanks

[davescm]

Select all the layers you are going to use and convert them to a single smart object (Layer>Smart Object>Convert to Smart Object). Then use stack mode.

Edit : Sorry, I just expanded your screenshot so I can now see the layers panel and just realised you already have the smart object.

Dave

[Jeff Arola]

Looks like there was a problem during the install, since the 3D menu is missing.

Are you using a 64 or 32 bit version of windows?

[Ronald Keller]

Does the activated smart object contains multiple layers?