Change Security stops my app from working

I have a Security Log-in page where the ID passed and used to limit the records to those belonging to the customer works just fine. I pass a Company code that is universal to all branches of that company. I can drill down to any child data with no problem
I take the same app and want to make a version where an Engineer can log-in and see ALL Companies on our database and go to a relevant Company and drill down.
All I did was change the security mode from "Users can see and edit their own data only" to "Users can see and edit other users data".
I log-on to the app with this single change. I can see a list of ALL Branches in my database. When I press any link to drill down to child data I get:-
"Microsoft OLE DB Provider for SQL Server (0x80040E14)

Cannot use empty object or column names. Use a single space if necessary.

/EngineersPortal_14/include/CompanyAddressCodeValid_masterlist.asp, line 47"
Here is the code in that Include module
[codebox]<%

function DisplayMasterTableInfo_CompanyAddressCodeValid(params)
oldTableName=strTableName

strTableName="dbo.CompanyAddressCodeValid"
detailtable=params("detailtable")

set keys=params("keys")
dim xt

set xt = new XTempl
sqlHead="SELECT seq, [Root Company], [Location Code], Company, ad, [Work Phone] "

sqlFrom="FROM dbo.CompanyAddressCodeValid "

sqlWhere=""

sqlTail=""
where=""
if detailtable="dbo.WebFaultLog" then

where=where & GetFullFieldName("Location Code","") & "=" & make_db_value("Location Code",keys(1-1),"","")

elseif detailtable="MaintenanceContacts" then

where=where & GetFullFieldName("Location Code","") & "=" & make_db_value("Location Code",keys(1-1),"","")

elseif detailtable="dbo.Fault Reports" then

where=where & GetFullFieldName("Location Code","") & "=" & make_dbvalue("Location Code",keys(1-1),"","")

end if

if where="" then

strTableName=oldTableName

exit function

end if
str = SecuritySQL("Search")

if len(str)>0 then

where = where & " and " & str
sstrWhere=whereAdd(sqlWhere,where)

if sstrWhere<> "" then _

sstrWhere=" where " & sstrWhere & " "

strSQL= sqlHead & sqlFrom & sstrWhere & sqlTail
LogInfo(strSQL)

dbConnection=""

db_connect()

Set rsm = server.CreateObject("ADODB.Recordset")

Set rss = server.CreateObject("ADODB.Recordset")

rsm.Open strSQL,dbConnection,1,2

keylink=""

keylink=keylink & "&key1=" & my_htmlspecialchars(SafeURLEncode(dbvalue(rsm("seq"))))

[/codebox]
Line 47 is rsm.Open strSQL,dbConnection,1,2
My guess is that this code is referencing the master Key to provide to the detail record. But why would it not work EVENE if in "ALL Branches" mode I am selecting the same Branch as I have in Limited View mode where the limiting key is provided explicitly by the Login sequence?
Using v 6.1 766
Regards,
Stu