Question

I get the following error when i try to run a console program which calls a Workflow 4 activity I created. Note the workflow compiles and runs without issue when executed from unit Tests or embedded in another workflow.

Could not load file or assembly
‘Microsoft.Practices.EnterpriseLibrary.Logging.Database,
PublicKeyToken=31bf3856ad364e35’ or
one of its dependencies. The system
cannot find the file specified.

I am using EnterpriseLibrary 5.0 for logging and connection strings.

I notice that the path to the assemblies is as follows:

C:\Program Files (x86)\Microsoft
Enterprise Library
5.0\Bin\Microsoft.Practices.EnterpriseLibrary.*

Looking at the Assembly Binding Log is
see the following:

* Assembly Binder Log Entry (17/03/2011 @ 15:32:48) *

The operation failed. Bind result: hr
= 0x80070002. The system cannot find the file specified.

Assembly manager loaded from:
C:\Windows\Microsoft.NET\Framework64\v4.0.30319\clr.dll
Running under executable
C:\Development\Work\EquinoxeAISManagementSystemWorkflow\EquinoxeAISManagementSystemWorkflow.FeedManager\bin\Debug\EquinoxeAISManagementSystemWorkflow.FeedManager.vshost.exe
— A detailed error log follows.

=== Pre-bind state information === LOG: User = EQUINOXEAIS\pmckee LOG:
DisplayName =
Microsoft.Practices.EnterpriseLibrary.Logging.Database,
Version=5.0.414.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35
(Fully-specified) LOG: Appbase =
file:///C:/Development/Work/EquinoxeAISManagementSystemWorkflow/EquinoxeAISManagementSystemWorkflow.FeedManager/bin/Debug/
LOG: Initial PrivatePath = NULL LOG:
Dynamic Base = NULL LOG: Cache Base =
NULL LOG: AppName =
EquinoxeAISManagementSystemWorkflow.FeedManager.vshost.exe
Calling assembly :
EquinoxeAISManagementSystemWorkflow.ActivityLibrary,
Version=1.0.0.0, Culture=neutral,

PublicKeyToken=null.

LOG: This bind starts in default load
context. LOG: No application
configuration file found. LOG: Using
host configuration file: LOG: Using
machine configuration file from
C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config.
LOG: Post-policy reference:
Microsoft.Practices.EnterpriseLibrary.Logging.Database,
Version=5.0.414.0, Culture=neutral,
PublicKeyToken=31bf3856ad364e35 LOG:
GAC Lookup was unsuccessful. LOG:
Attempting download of new URL
file:///C:/Development/Work/EquinoxeAISManagementSystemWorkflow/EquinoxeAISManagementSystemWorkflow.FeedManager/bin/Debug/Microsoft.Practices.EnterpriseLibrary.Logging.Database.DLL.
LOG: Attempting download of new URL
file:///C:/Development/Work/EquinoxeAISManagementSystemWorkflow/EquinoxeAISManagementSystemWorkflow.FeedManager/bin/Debug/Microsoft.Practices.EnterpriseLibrary.Logging.Database/Microsoft.Practices.EnterpriseLibrary.Logging.Database.DLL.
LOG: Attempting download of new URL
file:///C:/Development/Work/EquinoxeAISManagementSystemWorkflow/EquinoxeAISManagementSystemWorkflow.FeedManager/bin/Debug/Microsoft.Practices.EnterpriseLibrary.Logging.Database.EXE.
LOG: Attempting download of new URL
file:///C:/Development/Work/EquinoxeAISManagementSystemWorkflow/EquinoxeAISManagementSystemWorkflow.FeedManager/bin/Debug/Microsoft.Practices.EnterpriseLibrary.Logging.Database/Microsoft.Practices.EnterpriseLibrary.Logging.Database.EXE.
LOG: All probing URLs attempted and
failed.

I have tried the following to resolve the issue:
– Setting ‘Specific version’ to False for all referanced EnterpriseLibrary assemplies
– Recreating the app.config using the EnterpriseLibrary config tool again (and again and again 🙁
– Deleting all references assemblies and adding them back in one by one.

I would be really grateful if anyone had further pointer as to how to debug this issue…..THANKS!

Answer 1

I see three possible issues…

1. Your app is x64 (C:\Windows\Microsoft.NET\Framework64\), is Microsoft.Practices.EnterpriseLibrary.Logging.Database x86 or x64? (never tried to do this so I’m not sure if it can be done or not)
2. Is this file being copied local on build? It has to be located in C:/Development/Work/[snip]/bin/Debug in order for the fusion loader to find it. Fusion won’t look under every directory.
3. It is in the GAC, but it is not in the directory mentioned in #2. Fusion must first find the assembly under the install directory before it will probe the GAC for the assembly, IIRC*.

*this behavior depends on how the assembly is loaded at runtime using a partial bind, i.e., not using the assembly’s strong name.