Now you have me wondering if it's a combination of DVDA 7 and a specific build of windows. I know after certain builds Microsoft broke things here and there that had worked prior.

Do you still have your project and are you able to load it successfully with the most current build of windows 10 by chance?

@AYColumbia This is probably the thread I was thinking of https://www.vegascreativesoftware.info/us/forum/avc-files-in-dvd-architect-7-0--127582/#ca793188

My Windows - Win 10 Home 22H2 Build 19045.2311

My DVDA - Build 100 (which is DVDA7)

Yes I have my old projects archived. Two of the following were originally done with DVDAStudio 5, the other with DVDA7. They all opened okay after finding the required files on my archive external drive. All sat at 90% for several minutes. I suspect that this was DVDA evaluating the files.

Project 1 - 22.8gb. 7 Page Menus, 20 Movie titles. You cannot see them all but they are there all ticked.

Project 2 - 21.8gb. 3 Page Menus, 16 Movie titles. Again you cannot see them all but they are there all ticked.

Project 3 - 20.0gb. 4 Page Menus, 21 Movie titles. Again you cannot see them all but they are there all ticked.

Also a current project (it takes me ages to have enough videos to fill a disk) opened okay with 13 titles.

It is a perplexing mystery why a few users have your problem.

@EricLNZ,

Thanks much for the info. I looked at that thread you linked and wow, I can't believe I'd have to make my material interlaced. Ugh...Looking at your snapshots and based on that thead info it looks like why you don't have issues, i.e., your sources are interlaced and not progressive. What a mess DVDA 7 is in terms of this issue. At least there is a solution, but I don't like it. :( Where your source is 25i interlaced, mine is 24p. I did go back and found a project where I actually had 8 titles and my sources there were 23.976p so there seems to be something DVDA can't handle well when the source is 24p.

What I'll probably do is re-encode my sources to 23.976 instead and see if this resolves it as I want to stay away from interlaced material. Thanks Eric.

My understanding is that at the time it was produced DVDA was complying with the Blu-ray specs which mainly required interlaced. It was not that DVDA was a mess. I'm not sure but believe that the Blu-ray specs have altered and 50p for us PAL users is now accepted in addition to 50i. But DVDA is a discontinued product so is unlikely to be updated to reflect any changes in the Blu-ray specs.

Does DVDA show your 24p as needing recompression but is okay with 23.976?

Yup, understand on the specs so probably added progressive support later but didn't test it well.

DVDA sees my files as compliant so no recompression needed.

DVDA sees my files as compliant so no recompression needed

Presumably you are referring to your 23.976 files as on checking I find 23.976 Progressive is a setting DVDA accepts.

Something new learnt today. But I'm PAL so of little use to me.

For the future you could consider working your editing in a 23.976P project and with your 24 fps material "Add at Project Framerate" if you are using Vegas. This will avoid frames having to be created/discarded but it means your source material will be slower by 0.1% which won't be noticed by most viewers. Unless there's music when music lovers with highly tuned ears might! But even then it's doubtful.

@AYColumbia Oops, I've just realised that DVDA7 does have 24 progressive as a setting so 24 fps should be accepted. Is your source material 1920x1080?

Edit: I've created three short 1080 24p files. AVC video and AC3 audio. One a combined m2ts file and two with Vegas MS17 steams. No problems. DVDA7 accepts them without recompression in a 1080 24p Blu-ray project.

Yes, my sources are all 1920x1080p and all load just fine with no issues and no recompression. Just can't load more than 7 titles.

Did you try making copies of the 3 short videos so you have 8 or 9 and then see if you run into the same issue trying to add them to a project? I would think the size of the files won't matter but you never know.

@EricLNZ,

I tried what I asked you about, i.e., created a small 23.976p file and duplicated it. Looks like a 23.976p project can load 10 files and then goes to crap on the 11th title.

@AYColumbia I'll have a play later today with both 24 and 23.976.

@AYColumbia I created 12 - 1080 23.976fps AVC files plus audio streams and 12 - 1080 24fps AVC files plus audio streams. Used Sony AVC template modified and AC3 stereo.

Added the 23.976fps files to a 23.976P DVDA project and the 24fps files to a 24P DVDA project. No problems with either. But this isn't a good test as the files were small.

I wonder about HD space. DVDA needs at least twice the eventual disk size. How much free space on the drive you have set DVDA to use for temporary files and on the drive where the final iso file will be written to?