can't read, error -3420 (unknown)

[curioffl 1]

I have been getting these errors every Exchange mailboxes run:

 

File "Guys Name\Contacts\00000000e3d017b50f46d549a6bffe5893dc94f60700f2c6d908024f6b46adfc7fb63a571183000000103b4b0000f2c6d908024f6b46adfc7fb63a57118300000015ba010000": can't read, error -3420 (unknown)

 

If there's an errant contact is there any way to convert the long-numbers to tell us which one it is (the user has many)? Maybe we could delete it and add it again?

 

If not is there any "Universal" exclude variable that can be set just to skip these three contacts?

 

We are using 7.6.123. Would upgrading help?

 

Thanks.