PRB: COM Objects Fail to Print When Called From ASP

ID: Q184291

The information in this article applies to:

SYMPTOMS

A COM object that sends output to a printer fails when called from Active Server Pages (ASP), but functions correctly when called from an interactive application. This COM object could be either a commercial product such as a Microsoft Office application, or a custom third-party object. A common error message is "ClassName error '800a01e2' Printer error."


CAUSE

The standard APIs that most objects use to print depend on registry entries located in HKEY_CURRENT_USER. This registry hive is dynamic. Depending on which user context the process is running under, different information will be loaded into this hive. ASP pages run under IIS, which is running as the SYSTEM account. When you create an instance of a COM object in your ASP code, by default, it will also run as the SYSTEM account. By default, the SYSTEM account does not have any printers set up in the registry.


RESOLUTION

There are two ways of solving this problem. The first method is to configure the Windows NT Server to instantiate the COM object as a specific user rather than the same user as the process creating the instance. The second method is to set up printers for the SYSTEM account.

Method 1: Running the Object as a Specific User

If the COM object is implemented as an InProc server (a DLL), you can install the object into a package in Microsoft Transaction Server, and configure that package to run as a specific user.
  1. Launch the Transaction Server Explorer by selecting Programs from the Start button. Then select Windows NT 4.0 Option Pack, Microsoft Transaction Server, and Transaction Server Explorer


  2. Right-click the Packages Installed folder, and select New and then Package.


  3. Click on Create an Empty Package.


  4. Give the package a name.


  5. Choose to run the package as This user, and supply account and password information.


  6. Expand your new package by right-clicking the Components folder, and selecting New and then Component.


  7. Click Import components that are already registered.


  8. Find your components in the list, and select them.


  9. Click Finish.


If the COM object is implemented as a LocalServer (an EXE), you can configure that object using Dcomcnfg.exe to run as a specific user.
  1. Launch DCOMCNFG by clicking the Start button, selecting Run and typing Dcomcnfg.exe in the Run dialog box.


  2. In the Applications tab, find your component and click on the Properties button.


  3. On the Identity tab, select to run the application as This user:, and supply account and password information.


Method 2: Installing Printer(s) for the SYSTEM account

This method requires you to modify the registry using the Registry Editor.

WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall Windows to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.
  1. Ensure that the user you are currently logged into on the server has the desired printers installed.


  2. Launch the Registry Editor (Regedit.exe).


  3. Select the following key:
    
      HKEY_CURRENT_USER
         \Software\Microsoft\Windows NT\Current Version\Devices


  4. From the Registry menu, click Export Registry File.


  5. In the File Name text box, type c:\Devices.reg.


  6. Select the following key:
    
      HKEY_CURRENT_USER
         \Software\Microsoft\Windows NT\Current Version\PrinterPorts


  7. From the Registry menu, click Export Registry File.


  8. In the File Name text box, type c:\PrinterPorts.reg.


  9. Select the following key:
    
      HKEY_CURRENT_USER
         \Software\Microsoft\Windows NT\Current Version\Windows


  10. From the Registry menu, click Export Registry File.


  11. In the File Name text box, type c:\Windows.reg.


  12. From the Start button, select Run. Open Devices.reg in Notepad by typing Notepad Devices.reg in Run dialog box.


  13. Replace the text HKEY_CURRENT_USER with HKEY_USERS\.DEFAULT


  14. Save the file. Then import it into the registry by double-clicking the file in Windows Explorer.


  15. Repeat steps 13 through 15 for PrinterPorts.reg and Windows.reg.



REFERENCES

For the latest Knowledge Base articles and other support information on Visual InterDev and Active Server Pages, see the following page on the Microsoft Technical Support site:

http://support.microsoft.com/support/vinterdev/

For additional information, please see the following article in the Microsoft Knowledge Base:
Q152451 : Applications Run from the Schedule Service Fail to Print



(c) Microsoft Corporation 1998, All Rights Reserved.
Contributions by John Lewis, Microsoft Corporation. 


Keywords          : kberrmsg kbASP kbASPObj kbCOMt kbSecurity kbGrpASP 
Version           : WINNT:
Platform          : winnt 
Issue type        : kbprb

Last Reviewed: May 27, 1999