We have a reportserver on sql server 2005, it has previously been working on computer X which we are replacing with a computer Y. Computer X only had one default sql instance as our test environment, machine Y is a new machine with 2 sql instances, Y\TEST and Y\DEV. Both machines run Windows Server 2003 and Both have Sql Server 2005 installed together with Report Server We have not currently done any work on the DEV instance, just on the TEST instance. The reportserver is installed for TEST. SSRS previously worked as intended on X machine, and on Y\TEST its working for reports not using any custom code. However for some of the reports we are loading a custom assembly Localization. This assembly currently exists in following folders on server: C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\PublicAssemblies C:\Program Files\Microsoft Visual Studio 8\Common7\IDE\PrivateAssemblies C:\Program Files\Microsoft SQL Server\MSSQL.2\Reporting Services\ReportServer\bin Also in rssrvpolicy.config, the entry for Report_Expressions_Default_Permissions has been changed from Execution to FullTrust (Although this was not necessary on the machine X). When attempting to upload the rdl files through the web interface, we get the following errors: Error while loading code module: ‘Localization, Version=1.0.0.0, Culture=neutral, PublicKeyToken=e302ddd55ecd694a’. Details: Could not load file or assembly 'Localization, Version=1.0.0.0, Culture=neutral, PublicKeyToken=e302ddd55ecd694a' or one of its dependencies. The system cannot find the file specified. (rsErrorLoadingCodeModule) Get Online Help There is an error on line 14 of custom code: [BC30451] Name 'Localization' is not declared. (rsCompilerErrorInCode) Get Online Help Does anyone know any other places with potential errors?