Error 54 on file access

I am trying to open and save a file (some settings) on OS X 10.13.6 (High Sierra) into the ‘4D Folder’ which is:
DiskDrive : Users : Username : Library : Application Support : 4D

When either trying to open or save the settings (Blob to Document, or Document to Blob) I am getting the system(?) error 54.

-54 is a file access issue - open, locked, or permissions - but I can not find an error description for (positive) error 54.

Any help out there?

Thanks in advance

post some lines of code, they could help to avoid searching in the wrong direction.

Then, don’t care for error numbers, they are often not helpful, as more and more libraries are using the same error numbers. Use error strings…

If you are using On ERR CALL, fetch the whole error stack and report that. Else, if you get 4D’s error dialog, click expand to see the whole error stack.
Post the complete error stack here…

Maybe both (readBlob and writeBlob)
“DOCUMENT-TO-BLOB” and “BLOB-TO-DOCUMENT”
needs full access privileges (read+write)
https://doc.4d.com/4Dv18R3/4D/18-R3/DOCUMENT-TO-BLOB.301-4901405.en.html

Error Handling

  • If you try to load (into a BLOB) a document that does not exist or that is already open by another process or application, the appropriate File Manager error is generated.
  • An I/O error can occur if the document is locked, located on a locked volume, or if there is problem in reading the document.
  • If there is not enough memory to load the document, an error -108 is generated.

https://doc.4d.com/4Dv18R3/4D/18-R3/OS-Systemfehler-124-33.300-4901940.de.html
Translated DE-Doku-Site:
(-54) An attempt was made to open a locked volume in write mode.

https://doc.4d.com/4Dv18R3/4D/18-R3/OS-File-Manager-Errors-124-33.300-4901940.en.html
From EN-Doku-Site:
(-54) Attempt to open locked file for writing.

you can also lookup apple header files.

in principle, all (system) error codes are negative.

54 in 4D is a syntax error, but maybe something else is happening.

in addition to the good old ERROR system variable, perhaps you could investigate ERROR METHOD, ERROR LINE, ERROR FORMULA or GET LAST ERROR STACK.

Thanks everyone - I will see what I can find.