Runtime Error 2105: You can't go to the specified record

Sounds like you have Allow Additions set to No.

My Allow Addtions,Deletions,Edits and Filters are all set to Yes.
I have a field that does not allow duplicates.
Only once I go into design view after adding data it warns me about Duplicate values in the record, but if I Add the record with a button with this command : Docmd.Gotorecord,,AcNewRec I get the runtime error.  If I remove the duplicates to allow in the table the code works fine.  But I would like the field to be indexed to no duplicates.

Do you have data already in the Table that has duplicates?

No I don't have duplicates in the table, but I was checking my form to see that everything works correctly, if a user try's to add a duplicate that the record will not be accepted.

If you open up the Form manually and try and add a Record what happens?

The form opens no problem, I can add records no problem and the button works perfectly.  Only once the specific field gets a value that is already in the table from a previous record, is when the button to add a record gives me a runtime error, if I put error resume next in front of the code, nothing happens, no standard warning about duplicate values, the only time I get a message is when I go back into design view, then Access warns me that a duplicate value is in a field.  Bear in mind there is no special code to detect duplicates on my form, the only place is in the table for that specific field I have said the index to no duplicates.

Run down the troubleshooter. Could be something weird like you need to compact/repair.