QuickReport throws "There Is No Default Printer Currently Selected" Exception
I have created a Delphi Service which prints TQuickReports. Everything works fine if compiled and run as a Windows Application. But when converted to operate as a service trying to create a form containing a TQuickRep component throws the exception.
This service runs fine开发者_StackOverflow on many other boxes but not this one in particular. Here are some details:
- Using QuickReport version 4.07
- Box is a Windows Server 2008 operating system.
- Using Delphi 2007
- Printer.Printers.Count is returning a positive value. In fact I can list out all of the printers.
- I have tried running the service both using Local System Account and Logged on as an Admin.
Is there a default printer set up in session 0? Remember that under Vista / Server 2008 / Windows 7, services run in a separate session. Whether or not the logged-in user has a default printer set is not relevant - it's a per-session setting and doesn't affect session 0.
Can you rewrite the code to gracefully handle that exception and pick a printer to use?
You can solve this problem by creating a new dword UserSelectedDefault with the value: 1 in HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\SessionDefaultDevices\Session_ID
Make sure you have a local printer selected.
You might give the user a way to select the printer for the service. The Windows service probably does not have a default printer set.
Set TQuickRep.PrinterSettings.PrinterIndex
to set the printer number. Then, TQuickRep.Print
to print the report.
A colleague ended up finding the solution. I should have added these are "network" printers and not Local printers (at the time I didn't think this was related to the problem). So the service needed to be installed with "NetworkService" as the user account under the logon tab. From the Windows Help:
To specify that the service uses the Network Service account, click This account, and then type NT AUTHORITY\NetworkService
We had a simular problem here. Using TS servers, Citrix and Powerfuse 9. Powerfuse had all printers capitalized, however they were shared in a mixed case. This combination caused Delphi/QReport to crash
When all printers are from printserver to powerfuse in the same case (not important upper or lower or even mixed), the problem was gone
Actually it is a Delphi(5) problem. The comparison of the available printers and the default printer is case sensitive (Printers.pas):
if TPrinterDevice(Objects[I]).Device = Device then
begin
with TPrinterDevice(Objects[I]) do
SetPrinter(PChar(Device), PChar(Driver), PChar(Port), 0);
Exit;
end;
Changing the comparison to:
if lowercase(TPrinterDevice(Objects[I]).Device) = lowercase(Device)
solves the problem.
If using terminal services 2008, same user for multiple sessions, you should look into the:
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\SessionDefaultDevices\Session_ID
instead of
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows\
I solved a similar problem: If a Delphi application (or service) uses QuickReport, it runs before the system loads the default printer (or printers).
- When QuickReport executes
TQRPrinter.Init
, theprinter.printers.count
is zero, - shortly after the system loads, the
printer.printers.count
is the number of printers, - but
tqrprinter.int
has already executed, soTQRPrinter.FPrinterOK
is false, - you then see this error when you try open a QuickReport.
The solution for me was wait until the printers were loaded before launching the application (in citrix and terminal server). I solved this in two ways, either by overwriting tqrprinter
or delay the dpr
.
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