I am getting this error -2147467259 Unexpected Error from external database driver when running a vba macro code at this line-.Provider = "Microsoft.ACE.OLEDB.12.0"
in below code-

MyConn = _
"Data Source=" & ThisWorkbook.FullName & ";" & _
"Extended Properties=Excel 12.0;"

Set Cn = New ADODB.Connection
    With Cn
        .Provider = "Microsoft.ACE.OLEDB.12.0"
        .Open MyConn
    End With   

This is a simple vba macro (not using .net,sql server or ms access). Only excel is used. This works fine in following combinations- Excel 2007 & Windows Xp, Excel 2007 & Windows 7. But in Windows 7 and Excel 2010 it gives this error if the user is not admin. Interestingly, in Windows 7 and Excel 2010, if i login through admin user OR RUn excel.exe by clicking "Run as administrator" option (start-typoe excel-shift +right click-run as administrator)and then opening my excel file it does not give this error and more interestingly if after logging once through admin user and opening this excel file and closing it, I then log off and log in as normal user and open my excel file I still do not get this error.So the thing is that ONE TIME login as admin and opening this excel file temporariily fixes the issue.BUT the problem is that i need to distribute this application to various users and they will be logging it as normal users and i can not ask them to first login as admin user. Why this issue is ioccuring and what is the resolution for this? It’s very urgent , will really appreciate quick response.thanks.