Jet database access problem from web service

[Sonya]

Hello,

I have trouble connecting to Access database from my web service. Database
is located in a subdirectory of where service pages are. Code below produces
the following exception: "No error information available - E_NOINTERFACE".

[WebMethod(Descr iption = "This method tests connection",
EnableSession = true,
TransactionOpti on=TransactionO ption.RequiresN ew)]
public bool TestConnection( )
{
// Get connection string from web.config
string strConnection =
ConfigurationSe ttings.AppSetti ngs.Get("Connec tionString");
// Here's actual connection string
// "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=c:\WebSe rviceLocation\D ata\Data.mdb;Je t OLEDB:Database
Password=testpa ssword"
string username =
System.Security .Principal.Wind owsIdentity.Get Current().Name;

if (strConnection == null)
return false;

OleDbConnection conn = new OleDbConnection (strConnection) ;
try
{
conn.Open();
return true;
}
catch(Exception exc)
{
return false;
}
finally
{
conn.Close();
}
}

I tried a number of permission changes. I granted ASPNET account full
permissions into the directory where database is located; I granted
IUSR_MachineNam e account the same set of permissions; I tried impersonating a
normal user who has full permissions over Data directory; tried having Asp
process run under System account by modifying Machine.config. None of these
work and I always get the E_NOINTERFACE. (I did check this code out of
regular WinForms app and it works just fine).

I also tried an Odbc connection with with the follwoing string:
@"Driver={Micro soft Access Driver
(*.mdb)};Dbq=c: \WebServiceLoca tion\Data\Data. mdb;Uid=Admin;P wd=testpassword "
That gets me the following error:
"ERROR [25000] [Microsoft][ODBC Driver Manager] Failed to enlist on calling
object's transaction\r\n ERROR [IM006] [Microsoft][ODBC Driver Manager]
Driver's SQLSetConnectAt tr failed"

I am at a loss as to what to do. Any suggestions will be greatly appreciated.

Sonya

[Sonya]

Hey folks,

Dunno if anyone cares, but I found the problem. In the Webmethod attribute,
there is a named parameter TransactionOpti on=TransactionO ption.RequiresN ew.
Well, seeing as Access doesn't suport transactions, it was killing even the
connection. Having removed that, everything works.

Sonya

"Sonya" wrote:

Hello,

I have trouble connecting to Access database from my web service. Database
is located in a subdirectory of where service pages are. Code below produces
the following exception: "No error information available - E_NOINTERFACE".

[WebMethod(Descr iption = "This method tests connection",
EnableSession = true,
TransactionOpti on=TransactionO ption.RequiresN ew)]
public bool TestConnection( )
{
// Get connection string from web.config
string strConnection =
ConfigurationSe ttings.AppSetti ngs.Get("Connec tionString");
// Here's actual connection string
// "Provider=Micro soft.Jet.OLEDB. 4.0;Data
Source=c:\WebSe rviceLocation\D ata\Data.mdb;Je t OLEDB:Database
Password=testpa ssword"
string username =
System.Security .Principal.Wind owsIdentity.Get Current().Name;

if (strConnection == null)
return false;

OleDbConnection conn = new OleDbConnection (strConnection) ;
try
{
conn.Open();
return true;
}
catch(Exception exc)
{
return false;
}
finally
{
conn.Close();
}
}

I tried a number of permission changes. I granted ASPNET account full
permissions into the directory where database is located; I granted
IUSR_MachineNam e account the same set of permissions; I tried impersonating a
normal user who has full permissions over Data directory; tried having Asp
process run under System account by modifying Machine.config. None of these
work and I always get the E_NOINTERFACE. (I did check this code out of
regular WinForms app and it works just fine).

I also tried an Odbc connection with with the follwoing string:
@"Driver={Micro soft Access Driver
(*.mdb)};Dbq=c: \WebServiceLoca tion\Data\Data. mdb;Uid=Admin;P wd=testpassword "
That gets me the following error:
"ERROR [25000] [Microsoft][ODBC Driver Manager] Failed to enlist on calling
object's transaction\r\n ERROR [IM006] [Microsoft][ODBC Driver Manager]
Driver's SQLSetConnectAt tr failed"

I am at a loss as to what to do. Any suggestions will be greatly appreciated.

Sonya