Since you eliminated Privileges....
The "another User" part is usually caused by a window (layout) that is hidden from view and a field is still active (cursor blinking).
Thus the record is "in use".
Try Commit record script step before you Hide Window.
I suggest running a recover on the file to see what is reported by that process.
Thanks for the responses.
I ran a recover and it said that it recovered with no errors found. I then tried the same relookup on the recovered database (again logged in as Admin) and had the same problem.
I am not sure I understand the Commit record script step. I don't have any scripts, and I have triple checked that I don't have any other windows hidden. I also went through every layout that I have and made sure that there were no active fields/portals.
900 records is a large number of records to be locked out of by "edit" locks on data. It is possible, but not if this is a single user database and you have only one window open.
Are you sure that you have full access to the data? Any chance that this data is from a table in another file?
This is the process I just went through:
I just made a Test table (fk_specimenID, ref_specimen, random_var) and set up my relationships exactly as I described for the table I am struggling with. Then hand populated a few ref_SpecimenID values and did a Replace Field Contents by calculation and it worked. I then tried to Replace Field Contents by calculation using the same structure and it still gave me the "record(s) could not..." error.
Ok. So I have just built a replicate table and reimported the data into that. Then ran the same process and it worked. I have no idea why this would not work in the original table.
Thank you very much for your help.