Found the solution....

http://umbraco.codeplex.com/workitem/28080

Updating the lucene.net.dll sorted it, althought the binary attached is 2.9.2.2 and not 2.9.3 as posted. Unless it's just the details on the dll that haven't been updated.

Content seems to be publishing now...

Is this still working for you? 

I'm trying to install 4.5.1 for asp.net 3.5 on Rackspace Cloud, and having no luck.  It sounded like 4.5.1 is supposed to work in medium trust and have all these fixes you mention rolled in, but something is wrong.  The links to the 4.0.3 medium trust build are gone as well...

I have customErrors set to off but it still won't even show me the exception trace.

I haven't tried 4.5.1 physically  on the cloud as yet... but am running it locally with the rackspace medium trust settings.

Will post when I get around to updating the cloud version.

I'm currently trying to install 4.5.2 for ASP.NET 3.5 (Medium Trust) on the Rackspace Cloud and while I have no problem installing it and creating pages, I do have problems with the Umbraco Package Repository. I then read up on the forums here and found this post:

http://our.umbraco.org/forum/getting-started/installing-umbraco/10735-Using-Medium-Trust-on-Shared-Hosting-account-with-version-450

which lead me to 

http://umbraco.codeplex.com/workitem/28080

I tried using the attached Lucene.Net.dll file, and also tried building it from the SVN link provided and both did not work.  I'm still getting the following error when trying to access the Package Repository:

Server Error in '/' Application.
Security Exception
Description: The application attempted to perform an operation not allowed by the security policy.  To grant this application the required permission please contact your system administrator or change the application's trust level in the configuration file.

Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

Source Error:

[No relevant source lines]


Source File: App_Web_browserepository.aspx.5d1c7564.8yrhttjy.0.cs    Line: 0

Stack Trace:

[SecurityException: Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.]
   System.Security.CodeAccessSecurityEngine.Check(Object demand, StackCrawlMark& stackMark, Boolean isPermSet) +0
   System.Security.CodeAccessPermission.Demand() +58
   System.IO.Directory.InternalCreateDirectory(String fullPath, String path, DirectorySecurity dirSecurity) +595
   System.IO.Directory.CreateDirectory(String path, DirectorySecurity directorySecurity) +150
   System.IO.Directory.CreateDirectory(String path) +6
   umbraco.cms.businesslogic.packager.Settings.HasFileAccess(Exception& exp) +292
   umbraco.presentation.developer.packages.BrowseRepository.Page_Load(Object sender, EventArgs e) +110
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +14
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +35
   System.Web.UI.Control.OnLoad(EventArgs e) +99
   umbraco.BasePages.BasePage.OnLoad(EventArgs e) +49
   System.Web.UI.Control.LoadRecursive() +50
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +6785
   System.Web.UI.Page.ProcessRequest(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +242
   System.Web.UI.Page.ProcessRequest() +80
   System.Web.UI.Page.ProcessRequestWithNoAssert(HttpContext context) +21
   System.Web.UI.Page.ProcessRequest(HttpContext context) +49
   ASP.umbraco_developer_packages_browserepository_aspx.ProcessRequest(HttpContext context) in App_Web_browserepository.aspx.5d1c7564.8yrhttjy.0.cs:0
   System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +181
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +75


Version Information: Microsoft .NET Framework Version:2.0.50727.4206; ASP.NET Version:2.0.50727.4016 

I think you might have fallen foul of the bug with MS FILEIO and folder generation in clustered environments in .net3.5/ .net2.0

(basically in medium trust in on the cloud FILEIO can't create folders :-( ) http://cloudsites.rackspacecloud.com/index.php/Overview_of_modified_Medium_Trust#FileIO

Whilst that wiki says the only work around is ftp folder creation that's not actaully true.

If you raise a ticket to ask them to add "symbolic links" for the site in question, that should sort your issue.

(ps I presume you are already using impersonation)

Edit: This post is unnecessary.

Actually, ignore that last post. I thought I had impersonation enabled, but I must have removed it at some point for some reason. I added it and now it's working. Slowly, but it's working.  Thanks so much for your help!

I wanted to mention that I've been seeing the same issue, but only intermittently. With one site, I was able to install packages without issue, another I was unable to, and a third I cannot even open the package tree. I'll check back here as I progress along.

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