Excel file not doing read-only when accessed by multiple users, creates empty folders

[jabo4600]

This is in regards to Excel on a Mac running High Sierra with all updates completed. I work in a research lab and we use an Excel file to enter data. The file is saved on a server that multiple people access from different locations. Usually if someone else has it open, it will only open in read-only. Lately, if a second person tries to open it, a message pops up that says:

"Alert. We found a problem with some content in 'file name.xlsx.' Do you want us to try to recover as much as we can? If you trust the source of this workbook, click Yes."

If you click Yes, another pop up says:

"Alert. The workbook cannot be opened or repaired by Microsoft Excel because it is corrupt."

At some point (we haven't been able to determine when, as it doesn't seem to be predictable) an empty folder is created, that has the same name as the Excel file but with a string of varying letters and numbers after it. Multiple empty folders like this are created every day. Some examples of the string of letters and numbers are as follows (I've started with the xlsx extension and have not included the full file name), notice that the first 12 characters repeat:

xlsx.sb-388634f5-whyS2F
xlsx.sb-388634f5-h0hqXF
xlsx.sb-388634f5-GUudM6
xlsx.sb-388634f5-hBFtWk
xlsx.sb-388634f5-rkVL5q

xlsx.sb-30dc7262-36Lomy
xlsx.sb-30dc7262-1I4KOA
xlsx.sb-30dc7262-BzfXuT
xlsx.sb-30dc7262-ZqrDyE

It seems like in general the first 12 characters of each string is the same if the folders were created on the same day, but definitely not always. Sometimes the string is the same over several days, or there are random other strings in the middle of the group of a different string. Any help is greatly appreciated!! This has been a problem for months and IT doesn't know why it's happening. Note that not all of the files in the attached screenshot are relevant, there is an SPSS file and one of the xlsx files is something else (the one that ends in JL.xlsx). The original Excel file that is the issue is the top file in the screen shot. Thank you!!

[ranman256]

you should look into using an Access database that allows multi users to access the data.

for excel, you can give a warning and kick them out....
open the workbook, enter VBE (alt-F11)
in the left pane , Projects, dbl-click the ThisWorkbook object
in the right pane, the code area, paste the following:

Private Sub Workbook_Open()
CheckIsOpenByAnother
end sub

Public Sub CheckIsOpenByAnother()
If ActiveWorkbook.ReadOnly Then
    MsgBox "The file is in use by another"
    ActiveWorkbook.Close False
End If
End Sub