Excel Interop & IIS: Permissions Issue: PlugPlayManager Security Failure

[JimLad]

Hi,

First of all I didn't design this website, but I have been asked to
fix it with the minimum fuss!

Website is using .NET on IIS6 with an Excel Interop to produce
reports. The website impersonates the user and anonymous access is
disabled. Once excel is loaded it stays loaded for the life of the web
application and is accessed through an application variable. As I say,
I didn't design this! Usage of website is very low - once a month for
management reports.

The main user is unable to access the site. He says it is an
intermittant problem but at the moment he's completely unable to
access this and gets a UnauthorisedAccessException on
Interop.get_Workbooks(). Trouble is from his permissions he looks like
a local admin like me - I'm working on the assumption that he's
clearly not! He was unable to launch the excel application.

Having read a few posts, I have now given him all Access and Launch
permissions in DCOM for Excel. He no longer gets the above error and
is now able to launch Excel (it appears in Task Manager processes).
However, no excel workbook is created and the webpage hangs. There is
a failure in the Security Log:

Event Type: Failure Audit
Event Source: Security
Event Category: Object Access
Event ID: 560
Date: 08/10/2007
Time: 16:41:43
User: CORP\firstname.surname
Computer: M05010072
Description:
Object Open:
Object Server: PlugPlayManager
Object Type: Security
Object Name: PlugPlaySecurityObject
Handle ID: -
Operation ID: {0,106320991}
Process ID: 416
Image File Name: C:\WINDOWS\system32\services.exe
Primary User Name: S05010072$
Primary Domain: CORP
Primary Logon ID: (0x0,0x3E7)
Client User Name: firstname.surname
Client Domain: CORP
Client Logon ID: (0x0,0x656452E)
Accesses: Unknown specific access (bit 0)

Privileges: -
Restricted Sid Count: 0
Access Mask: 0x1

What Plug and Play has to do with anything I really don't know but
it's a repeatable error.

Does anyone know what's going on? I've seen other posts with a similar
symptoms but they weren't answered.

Here's hoping! Many thanks in advance!

Cheers,

James

 

[Mark Rae [MVP]]

Website is using .NET on IIS6 with an Excel Interop
The website impersonates the user
Does anyone know what's going on?

Yup, but you're not going to like it...

Server-side Office automation isn't supported by Microsoft, because it
doesn't work:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;q257757#kb2

Impersonation just makes it even more unstable:
http://support.microsoft.com/default.aspx/kb/288367


Two possible solutions:

1) If you're just using Excel as a datasource, you can do that directly
through ADO.NET / OleDb

2) If you need to manipulate the Excel documents, you need this:
http://www.aspose.com/Products/Aspose.Cells/Default.aspx

 

[JimLad]

Yup, but you're not going to like it...

Server-side Office automation isn't supported by Microsoft, because it
doesn't work:http://support.microsoft.com/default.aspx?scid=kb;EN-US;q257757#kb2

Impersonation just makes it even more unstable:http://support.microsoft.com/default.aspx/kb/288367

Two possible solutions:

1) If you're just using Excel as a datasource, you can do that directly
through ADO.NET / OleDb

2) If you need to manipulate the Excel documents, you need this:http://www.aspose.com/Products/Aspose.Cells/Default.aspx

Thanks Mark. That makes things very clear!

Cheers,

James

 

[JimLad]

Thanks Mark. That makes things very clear!

Cheers,

James

Actually, one more question. Could I just use OWC11 (Office Web
Components) instead? I'm assuming that would sort of be a straight
swap and not too difficult?

Cheers,

James

 

[Mark Rae [MVP]]

Actually, one more question. Could I just use OWC11 (Office Web
Components) instead?

Possibly, depending on your version of Excel:
http://blogs.msdn.com/excel/archive/2006/07/17/668544.aspx

I'm assuming that would sort of be a straight swap and not too difficult?

I'm afraid I don't know enough about the subject to answer your question -
you could try posting on one of the Excel newsgroups...

 

[JimLad]

Possibly, depending on your version of Excel:http://blogs.msdn.com/excel/archive/2006/07/17/668544.aspx


I'm afraid I don't know enough about the subject to answer your question -
you could try posting on one of the Excel newsgroups...

Thanks very much for your help Mark.

James