It looks like I'm having the same problem, but I think I've come up with some significant information to narrow it down.

I'm getting the error:
It does this a) when I click the link for Forums on the administration page, and b) if I switch the site's default style to something other than subBlack and view the forums as an anonymous user. I think it's worth noting that I still get that exact message, regardless of what theme I switch to; e.g. I can change the nuke theme to Milo and it still says "can't find subBlack template".

I was using PHP-Nuke 6.0 with the phpBB port by Tom, then upgraded to nuke 6.5 by running the upgrade script found here on NukeMods. I have since upgraded to 6.7 in an attempt to fix it, to no avail.

I did a site search here and these are the other threads that look most relevant:
http://www.nukemods.com/modules.php?...te+config+file
http://www.nukemods.com/modules.php?...te+config+file
http://www.nukemods.com/modules.php?...te+config+file

After reading in that last one where MikeM says, "That message means that your Forums are using a template that is not in your modules/Forums/templates directory or doens't have a theme_info.cfg file" I checked the directory and sure enough, it only has a subSilver folder (as I imagine it should). When I looked at the 6.0 backup, I found that my modules/Forums/templates directory had only a subBlack folder.

This makes sense to me, because under my 6.0 install, I had added subBlack and removed all other themes (as I did not want users having the option to choose themes).

After uploading my old modules/Forums/templates/subBlack directory, I am now able to get into the forum admin, and mostly it seems to work ok. There are two exceptions:

1) in the upper left, just above the phpBB logo, I get this error:
Parse error: parse error, unexpected T_PRINT in
[my Nuke path]/modules/Forums/admin/admin_avatar.php on line 223

2) If I switch the site theme to something else (like Milo), and an anonymous user looks at forums, the nuke portions are in Milo (the left blocks, top header), but everything else (the forum part) is still in subBlack.

It seems to me that somewhere, the old phpBB theme settings are being used rather than whatever it is that nuke 6.5 is supposed to do. I purged all the old files before uploading 6.7, so I'm assuming this is a database issue and not a config file problem.

I have the opportunity to use the forum admin to switch its default theme, add subSilver back in, etc. but I'm not sure what this will do. I'm afraid it will just create the same problem with whatever theme I install, plus I dont really know if it will overwrite something else that Nuke is using.

So... I think I should have enough documentation of the problem here to get a prize or something... But I'd settle for an idea of what to do.

- H8