Error: The object "{object}" has been modified by another user in the meanwhile.

Question

Can anyone say where this error is coming from? It appears whenever a custom date metadata field is valued in version properties, and any edit is attempted to the version properties (that is, whenever the version properties panel is opened and "Modify" is pressed). If the date value is not set, the error does not occur.

This seems to be the relevant portion of InfoShareAuthor log corresponding to error:

00004484 <<< PRS API25 15:32:12.551 COMAPI25.User.GetMyMetadata start
00004484 >>> PRS API25 15:32:12.567 COMAPI25.User.GetMyMetadata end --> elapsed:15ms (ThreadId=3896)
00004484 ERR PRS RepDoc Time:15:32:12.567 TridkVersion:120.9.0.2417 Error: SDL Knowledge Center Content Manager 12.0.2417 Error: The object "{object}" has been modified by another user in the meanwhile.
00004484 ERR PRS RepDoc START PARAMETER LIST
00004484 ERR PRS RepDoc ====================
00004484 ERR PRS RepDoc object: 668259
00004484 ERR PRS RepDoc ====================
00004484 ERR PRS RepDoc END PARAMETER LIST
00004484 ERR PRS RepDoc RAISED IN: PRS.RepDoc.LogObject:\0\ISAuthor.RepDoc.Modify
00004484 ERR PRS RepDoc Time:15:32:12.583 TridkVersion:120.9.0.2417 Error: SDL Knowledge Center Content Manager 12.0.2417 Error: The object "{object}" has been modified by another user in the meanwhile.
00004484 ERR PRS RepDoc START PARAMETER LIST
00004484 ERR PRS RepDoc ====================
00004484 ERR PRS RepDoc object: 668259
00004484 ERR PRS RepDoc ====================
00004484 ERR PRS RepDoc END PARAMETER LIST
00004484 ERR PRS RepDoc RAISED IN: PRS.RepDoc.LogObject:\0\ISAuthor.RepDoc.Modify

Dave De Meyer · Accepted Answer

There is fully working date field on the Publication Output (so publication lng-level) called FISHPUBREVIEWENDDATE. Perhaps you can find inspiration in the variables, code and assist functions used on what you did differently compared to your custom date field FABSEDITIONDATE.

Dave De Meyer · Answer

The essence is that Web Client ClassicASP pages use a system of original-values and new-values to submit a change to the repository. If the original-values are not present or of the wrong type compared to the database, you can get this error. The system things somebody else changed your data in the meanwhile, but as it is about a custom field, my guess is that is what you'll need to investigate first. 
The typical prefix is ORIG-, like ORIG-FREQUESTEDLANGUAGES. 
 
If you have taxonomy fields (so IMetadataBinding) configured, then it becomes even a bit more complicated.

Tridion Docs Developers > 03 - Developer Forum

Error: The object "{object}" has been modified by another user in the meanwhile.