Excel service and OWA - getting ERROR while trying to open/edit Excel documents

Question

Hi All,
We have configured SharePoint 2013 with Excel Service and OWA (Office Web Apps).
After configuring, we are able to view/edit Word or PowerPoint documents from the browser (as OWA is configured). But we are getting errors while trying to open/edit Excel documents.
We are not able to view/edit the excel workbook from the browser (through OWA).
To open the excel in the browser, decision has to be taken at the farm level on what to be used – Excel Service or OWA Server? Is it possible to do setting at site collection level?
Error details are given below:
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 3/25/2013 1:29:08 PM
Event time (UTC): 3/25/2013 7:59:08 AM
Event ID: fc2e0530f493493896e6c8b6297a0423
Event sequence: 10
Event occurrence: 3
Event detail code: 0
Application information:
    Application domain: /LM/W3SVC/2/ROOT/x-1-130086717598089315
    Trust level: Full
    Application Virtual Path: /x
    Application Path: C:\Program Files\Microsoft Office Web Apps\ExcelServicesWfe\
    Machine name: VHYDMANTHSTP-02
Process information:
    Process ID: 1252
    Process name: w3wp.exe
    Account name: NT AUTHORITY\NETWORK SERVICE
Exception information:
    Exception type: ArgumentException
    Exception message: An entry with the same key already exists.
   at System.Collections.Generic.TreeSet`1.AddIfNotPresent(T item)
   at System.Collections.Generic.SortedDictionary`2..ctor(IDictionary`2 dictionary, IComparer`1 comparer)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.GetInstalledUICultures()
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.IsUICultureSupported(String cultureTag, CultureInfo& cultureInfo)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentUICulture(String cultureTag, Boolean useOleo, Boolean allowCustomFallback)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentUICultureFromFrontEnd(String uiCultureTag, Boolean allowFallback)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentCulturesFromFrontEnd(String uiCultureTag, String dataCultureTag)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.Microsoft.Office.Excel.Server.Host.IEwaHost.SetCurrentCulturesFromContext(HttpContext context)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.Microsoft.Office.Excel.Server.Host.IEwaHost.PreProcessRequest(HttpContext context)
   at Microsoft.Office.Excel.WebUI.XlPreview.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
Request information:
    Request URL:
http://mysrevr/x/_layouts/xlpreview.aspx?ui=en-US&rs=en-US&WOPISrc=http://myservernames1/_vti_bin/wopi.ashx/files/f36d669ceb814d67bdad0e1e1f98e466&wdSmallView=1
    Request path: /x/_layouts/xlpreview.aspx
    User host address: 10.81.138.92
    User: 
    Is authenticated: False
    Authentication Type: 
    Thread account name: NT AUTHORITY\NETWORK SERVICE
Thread information:
    Thread ID: 13
    Thread account name: NT AUTHORITY\NETWORK SERVICE
    Is impersonating: False
    Stack trace:    at System.Collections.Generic.TreeSet`1.AddIfNotPresent(T item)
   at System.Collections.Generic.SortedDictionary`2..ctor(IDictionary`2 dictionary, IComparer`1 comparer)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.GetInstalledUICultures()
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.IsUICultureSupported(String cultureTag, CultureInfo& cultureInfo)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentUICulture(String cultureTag, Boolean useOleo, Boolean allowCustomFallback)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentUICultureFromFrontEnd(String uiCultureTag, Boolean allowFallback)
   at Microsoft.Office.Excel.Server.ExcelServerRegionalSettings.SafeSetCurrentCulturesFromFrontEnd(String uiCultureTag, String dataCultureTag)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.Microsoft.Office.Excel.Server.Host.IEwaHost.SetCurrentCulturesFromContext(HttpContext context)
   at Microsoft.Office.Excel.Server.ServiceHost.ServiceHost.Microsoft.Office.Excel.Server.Host.IEwaHost.PreProcessRequest(HttpContext context)
   at Microsoft.Office.Excel.WebUI.XlPreview.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)

Answer 1

I have the same issue while opening the file , i have checked every thing twice. but unable to fix this thing . can any one help.
One more thing which is i am wondering none of the MS representative replied on this post which is originally posted on March 27-2013.
is microsoft alive??
Imran Bashir Network Administrator MCP, JNCIA-EX,ER,JNIOUS [phone]