Ahh new error now showing, does this mean it's Imageprocessor that is my issue? I can't uninstall it, nor change the version as Umb7.15 is dependent on it.

 2019-07-10 15:02:58,122 [P8776/D2/T9] ERROR Umbraco.Core.UmbracoApplicationBase - An unhandled exception occurred
System.IO.PathTooLongException: The specified path, file name, or both are too long. The fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters.
   at System.IO.PathHelper.GetFullPathName()
   at System.IO.Path.LegacyNormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
   at System.IO.Path.NormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
   at System.IO.Path.GetFullPathInternal(String path)
   at System.Security.Util.StringExpressionSet.CanonicalizePath(String path, Boolean needFullPath)
   at System.Security.Util.StringExpressionSet.CreateListFromExpressions(String[] str, Boolean needFullPath)
   at System.Security.Permissions.FileIOPermission.AddPathList(FileIOPermissionAccess access, AccessControlActions control, String[] pathListOrig, Boolean checkForDuplicates, Boolean needFullPath, Boolean copyPathList)
   at System.Security.Permissions.FileIOPermission..ctor(FileIOPermissionAccess access, String path)
   at System.Web.InternalSecurityPermissions.PathDiscovery(String path)
   at System.Web.Hosting.HostingEnvironment.MapPath(VirtualPath virtualPath)
   at System.Web.Hosting.HostingEnvironment.MapPath(String virtualPath)
   at ImageProcessor.Web.HttpModules.ImageProcessingModule.<ProcessImageAsync>d__31.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Web.TaskAsyncHelper.EndTask(IAsyncResult ar)
   at System.Web.HttpApplication.AsyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStepImpl(IExecutionStep step)
   at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)

And now in the console we get

Could not find the tree media, activeTree has not been set

Yes I get this issue too. Just upgraded myself to v7.15. Only affects my site using the UmbracoFileSystemProviders.Azure plugin.

Yep I only upgraded because of the security release.

I think it's to do with the UmbracoFileSystemProviders.Azure plugin as I upgraded another 3 sites and they are fine. It's only affected the media folders for the site using that azure media plugin.

I've pinged Jeavon and James on Twitter in case they had seen this, and asked Seb if there was a change in to the alllowed file lengths/names for media items.

Very strange, I can't imagine anything changes that might have caused this.

Can any of you post a full log file (or email it to sj @ umbraco.dk) ? Preferably with Debug level set to <add key="serilog:minimum-level" value="Debug" /> so we have more info.

Whoops, it's v7, <priority value="Debug"/> in the log4net.config file I mean. ;-)

I'm not seeing any errors in my log. Will email you regardless.

Seems to be a javascript error, I'm hearing back from another test.

Replied via email. But I have zero errors in my log which is weird.

Ah yes, looks like a server side issue after all, but not with any errors reported. How old are these websites originally? I have tried with a 7.12 site and that worked but I can repro on a really old site that has been upgraded over the years.

I have a site from 2016, which I just upgraded from 7.5.9 to 7.15 that has the same problem.

I can see 7.15 has some changes in the EntityRepository, that might be the problem (don't know how though). https://github.com/umbraco/Umbraco-CMS/commit/23b8e1cce8107aabd8ba5ebbcb0a3ee33aff212d#diff-f0fb88312c00e357c11d8d36264524d3

Based on the fact that both the treecontroller and the entityService API returns no folders.

No errors in the logs for me either, despite me trying to get it to happen for the purpose of sending a log file over.

I do, occasionally get javascript errors that have pointed to lib/angular 1.1.5, when these happen the console message is generally:

Could not find the tree media, activeTree has not been set

I also get a similar message about tree users and active tree when I tried to set the media start node on a group. When I set a start node to be one of the folders which isn't displaying Umb will save it, but on refresh of the page it's then blank again.

@Seb, the site I upgraded was a 7.14 site when I applied 7.15, but it's migration history is thus: 7.2.8 > 7.7.6 > 7.7.13 > 7.9.6 > 7.11.2 > 7.14 > 7.15

Thanks for tracking it down Seb.

About the SQL-fix uggested in https://github.com/umbraco/Umbraco-CMS/issues/5848.

 DECLARE @i int
 DECLARE @nodeId int
 DECLARE @numrows int
 DECLARE @versionId varchar(50)
 DECLARE @rootNodes TABLE (
     idx smallint Primary Key IDENTITY(1,1)
     , NodeId int
 )

 INSERT @rootNodes
 SELECT id FROM umbracoNode WHERE nodeObjectType = 'B796F64C-1F99-4FFB-B886-4BF4BC011A9C' AND id NOT IN (SELECT nodeId FROM cmsMedia)

 SET @i = 1
 SET @numrows = (SELECT COUNT(*) FROM @rootNodes)
 IF @numrows > 0
     WHILE (@i <= (SELECT MAX(idx) FROM @rootNodes))
     BEGIN

         SET @nodeId = (SELECT NodeId FROM @rootNodes WHERE idx = @i)

         --Do something with Id here
         SET @versionId = (SELECT TOP 1 VersionId FROM cmsContentVersion WHERE ContentId = @nodeId ORDER BY VersionDate DESC)
        PRINT(@versionId)
        PRINT(@nodeId)
        INSERT INTO cmsMedia(nodeId, versionId) VALUES(@nodeId, @versionId)

         SET @i = @i + 1
     END

Do notice that parentId = -1 has been removed from the original post, suggested by Lee (@YodasMyDad) in the Issue.

Does it (still) work for you? Any complications?

I am concerned since there is no traceability what so ever if we run the TSQL.

Preferred case would of course be if Umbraco made an official patch. Please do :)

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