Check the connection string for example these are not the same:

DisplaySQL.asp does:
oConnection.Open "DSN=QuickBooks Data;OLE DB Services=-2" ''This is the name of your System DSN
oRecordset.CursorLocation = adUseClient
oRecordset.Open sSQL , oConnection, adOpenStatic, adLockOptimistic

while qbcust.asp does:
oConnection.Open "QuickBooks Data"
response.write "QODBC DSN QuickBooks Data Open<BR>" & vbCrLf
response.flush

oRecordset.CursorLocation = adUseClient
oRecordset.Open "SELECT * FROM Customer" , oConnection, adOpenStatic, adLockOptimistic

qbcust.asp is one of my scripts. There's a updated version of DisplaySQL.php that can be found at: PHP samples or help?

See: How can I see QuickBooks data in a Internet Explorer Browser using Windows XP?  for the setup info behind using QODBC via IIS. Most issues have to do with security setup. What type of security have you setup on the server? There can be all sort of permissions issues with IIS using AUTHENTICATED USERS. Sometimes the *shotgun* approach of giving everything that has the words QODBC in it is the only way....

See the last post in: Permissions Issue with IIS using AUTHENTICATED USERS