Publisher: "Save failed because control of the lock file was lost" – what's going on here?

[Lorox]

I've recently been working on two files (both originally InDesign resp IDML files) in Publisher 2.5.6 (on Mac with Monterey) and after some time of making several tweaks I then haven't been able to save them and instead got the alert as seen in the attached screenshot.

I had been able to open the files from their IDML versions with no problems at all and they were looking faithful to the InDesign originals as well. While working on them I repeatedly saved them as to save changes made so far.

After exporting preview PDFs for my client I I finally wanted to save and close the Publisher files for the day but actually couldn't and the alert you see attached popped up.

I had saved quite frequently before and after relaunching Publisher the files could actually be opened normally and could be saved (and "saved as…“) again as well. So fortunately nothing has been really lost.

But it's quite embarrassing, nevertheless, when after working for some time on a file you get that alert when you want to save the current state...

I had never before encountered something like this and I'm quite a loss for possible explanations. What's that "lock file“ the "control" of which had allegedly been lost, anyway?

[Lorox]

I forgot to add that "Save as" – after that alert had appeared – didn't actually work neither...

[Pšenda]

4 minutes ago, Lorox said:

I had never before encountered something like this and I'm quite a loss for possible explanations. What's that "lock file“ the "control" of which had allegedly been lost, anyway?

https://www.google.com/search?q=Save+failed+because+control+of+the+lock+file+was+lost+site:https://forum.affinity.serif.com

[Lee D]

@Lorox This FAQ article explains what a 'lock' file is, but it's basically prevents the file from being opened/accessed by other users.

Was you saving this file locally or to a cloud or networked location? As this may explain why access to the lock file was lost.

When you clicked Save As what happened? Did you receive any other messages?

[Lorox]

2 hours ago, Lee D said:

Was you saving this file locally or to a cloud or networked location? As this may explain why access to the lock file was lost.

When you clicked Save As what happened? Did you receive any other messages?

No, I was saving (or at least tried to save) to my internal SSD.

If I remember correctly "Save as…" produced the same alert when I chose another location on my internal disc (e.g. just "Desktop"). However, when I saved to another computer via LAN it seemed to work at first – but it turned out that Publisher could not open the resulting file... (said something like: "no valid [data] format"; can't really remember)

As this all hadn't ever happened before in years of using Publisher I – of course – tried to think of what these specific files had in common:
both were originally IDML files exported from InDesign, with both of them I initially had to relink up to 3 images and with both of them I had at one time exchanged/relinked 1-bit bitmap TIFFs (from the original InDesign way of doing things) to Grayscale PNGs (with transparent background) which were then assigned a CMYK colour in Publisher (using the “K only“ feature). However, in one of these Publisher files these PNGs had later been exchanged for native vector graphics, so there was just a regular linked CMYK-TIFF left.

When that failure to save occured, I also copied the content from the affected file to a fresh Publisher document (which actually could be saved). Strangely though, I noticed that just by that copying all these elements the stroke width of one rounded rectangle had miraculously changed from 2pt to 4pt and the font size in one frame text element had also doubled for no apparent reason.

Another thing:
After copying the content from Publisher to a fresh Designer(!) document – just to try things out – literally all previous organisation of elements using groups and layers was completely gone and everything in the layers pallette was just basic curves, rectangles etc.. It was still looking OK, so all of the stacking order of things had obviously been preserved, but all the structuring, which had been there in Publisher, was gone. As the Affinity apps are said to have the same data format internally this has been a bit surprising to me.