Exchange ECP loads but OWA error The item you tried to access no longer exists. The item wasn't found. You or a delegate might have moved or deleted it using another computer or a mobile phone.

Already tried rebooting both exchange servers but no luck. Still owa is throwing same error.

It is for all mailboxes, if it is for only one mailbox i wont be much worried would have tried moving the mailbox to another database.

Try local host /OWA and see if it works

i tried already local host, only on this server owa is not working but on the secondary the owa works fine. I think something wrong with the primary server owa virtual directory. Any suggestions?

Try running the casrepair.ps1 this should reinstall the binaries if there is any corruption

This would be available under the scripts folder

But presently ecp is running fine in the primary server, only owa is a problem. Moreover smtp communication and pop3, imap clients are fine. Does this casrepair.ps1 affect anything ?

Also i couldn't run find the script which you specified.

No it would just re-register the .dll

Give a try it may help you ,I will check in my LAb and will post you

I couldn't find that ps1 file in script directory

ECP works fine and only owa. I tried recreating the owa virtual directory, rebooted server multiple times.Verified IIS settings on both default and Exchange Backend virtual directory comparing with working ECP directory and another working server. In secondary exchange server OWA & ECP works properly. We are facing only OWA issue in primary and moreover all the mailboxes are in secondary. All arbitration mailboxes are in primary server.

I tried accessing locally https://servername/owa which prompts for login page and once password is keyed in then it throws error. Mostly pop and IMAP users, and few or Outlook anywhere clients. Both Exchange servers is running with CU4 and i am unable to update because of hardware reasons.

IE :
The item you tried to access no longer exists.
The item wasn't found. You or a delegate might have moved or deleted it using another computer or a mobile phone.  

Chrome: https://domain.com/owa/auth/errorfe.aspx?httpCode=500&msg=861904327
:-(
something went wrong
A problem occurred while you were trying to use your mailbox.
Want to be able to use your email when you're offline?
Next time you are connected:
1. At the top of Outlook Web App, next to your name, click Settings
2. Click Offline settings and turn on offline access
3. That's it! You'll never see this message again.

That's what looking at this error seems something wrong with the dll let me find the exact name of the script and share it to you

For testing, I also tried my mailbox moving to another database and checked getting the same error.

Another test i did,  i created new mailbox in the primary exchange database. When i tried to access owa, i get following error.  So used secondary exchange https://secondaryservername/owa and logged in i could login successfully. Perhaps the following error might throw some light.

An unexpected error occurred and your request couldn't be handled.
--------------------------------------------------------------------------------
 Show details
Request
Url: https://exch-svr.domain.com:444/owa/
User host address: ::1
OWA version: 15.0.620.22

Exception
Exception type: Microsoft.Exchange.Clients.Owa2.Server.Core.OwaADUserNotFoundException
Exception message:

Call stack

Microsoft.Exchange.Clients.Owa2.Server.Core.OwaIdentity.CreateOWAMiniRecipientBySid()
Microsoft.Exchange.Clients.Owa2.Server.Core.OwaWindowsIdentity.InternalCreateExchangePrincipal()
Microsoft.Exchange.Clients.Owa2.Server.Core.OwaIdentity.CreateExchangePrincipal()
Microsoft.Exchange.Clients.Owa2.Server.Core.UserContext.Load(OwaIdentity logonIdentity, OwaIdentity mailboxIdentity, serContextStatistics stats)
Microsoft.Exchange.Clients.Owa2.Server.Core.UserContextManager.CreateUserContext(HttpContext httpContext, UserContextKey userContextKey, ClientSecurityContext overrideClientSecurityContext, UserContext& userContext, UserContextStatistics& userContextStats)
Microsoft.Exchange.Clients.Owa2.Server.Core.UserContextManager.AquireUserContext(HttpContext httpContext, ClientSecurityContext overrideClientSecurityContext)
Microsoft.Exchange.Clients.Owa2.Server.Core.UserContextManager.GetUserContext(HttpContext httpContext, Boolean create)
Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.InternalDispatchRequest(RequestContext requestContext)
Microsoft.Exchange.Clients.Owa2.Server.Core.RequestDispatcher.DispatchRequest(RequestContext requestContext)
Microsoft.Exchange.Clients.Owa2.Server.Core.OwaRequestHandler.InternalOnPostAuthorizeRequest(Object sender)
Microsoft.Exchange.Clients.Owa2.Server.Core.OwaRequestHandler.OnPostAuthorizeRequest(Object sender, EventArgs e)
System.Web.HttpApplication.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)