Could not load file or assembly BCMLogon For SSRS

While configuring Reporting service with SharePoint i had found that Reporting Services is not available at Central Administration > General Application Settings 

So i have install the SSRS plugin Provided by Microsoft Microsoft® SQL Server® 2008 R2 Reporting Services Add-in for Microsoft SharePoint® Technologies 2010

And continue my steps to configure Reporting Services.

Now, while configuring Reporting service in SharePoint Integrated mode i have found that following error occurred on 

Central Administration > Reporting Services Integration  

Error: "Could not load file or assembly 'BCMLogon, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. Failed to grant permission to execute."

And In ULS Logs : "w3wp.exe (0x2B3C)                        0x24E0 Failed to retrieve RS configuration information: System.IO.FileLoadException: Could not load file or assembly 'BCMLogon, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' or one of its dependencies. Failed to grant permission to execute. (Exception from HRESULT: 0x80131418)  File name: 'BCMLogon, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' ---> System.Security.Policy.PolicyException: Execution permission cannot be acquired.     at System.Security.SecurityManager.ResolvePolicy(Evidence evidence, PermissionSet reqdPset, PermissionSet optPset, PermissionSet denyPset, PermissionSet& denied, Boolean checkExecutionPermission)     at System.Security.SecurityManager.ResolvePolicy(Evidence evidence, PermissionSet reqdPset, PermissionSet optPset, PermissionSet denyPset, PermissionSet... 75e37778-1659-4d36-b0cb-1acc7d1a14da

w3wp.exe (0x2B3C)                        0x24E0 SQL Server Reporting Services Configuration Pages            aabm High     ...& denied, Int32& securitySpecialFlags, Boolean checkExecutionPermission)     at Microsoft.ReportingServices.SharePoint.UI.ImpersonateUser.LogonUser(String lpszUsername, String lpszDomain, String lpszPassword, Int32 dwLogonType, Int32 dwLogonProvider, IntPtr& phToken)     at Microsoft.ReportingServices.SharePoint.UI.ImpersonateUser..ctor(String username, String password)     at Microsoft.ReportingServices.SharePoint.UI.RSIntegrationSettings.GetReportServerConfigInfo(IList`1& configInfos)     75e37778-1659-4d36-b0cb-1acc7d1a14da

w3wp.exe (0x2B3C)                        0x24E0 SharePoint Foundation          Topology                       8xqz Medium   Updating SPPersistedObject SPRSServiceConfiguration Name=ReportingService. Version: 1506150 Ensure: False, HashCode: 52430652, Id: e4fe0291-a851-4cf3-8638-c4d684def2c9, Stack:    at Microsoft.SharePoint.Administration.SPPersistedObject.BaseUpdate()     at Microsoft.ReportingServices.SharePoint.UI.RSIntegrationSettings.ApplyChanges()     at Microsoft.ReportingServices.SharePoint.UI.ReportServerSiteSettings.ApplyChangesClicked(Object sender, CancelEventArgs e)     at Microsoft.ReportingServices.SharePoint.UI.ButtonPageControl.OnApplyChangesClicked(CancelEventArgs e)     at Microsoft.ReportingServices.SharePoint.UI.ButtonPageControl.ApplyButton_Click(Object sender, EventArgs e)     at System.Web.UI.WebControls.Button.OnClick(EventArgs e)     at System.Web.UI.WebControls.Button.RaisePostBackEv... 75e37778-1659-4d36-b0cb-1acc7d1a14da"

and after wasting much time i have found that this Error was due to Permissions i.e.

1. Password Of Service account has been expired/Modified.[My Case].
2. The Logged In user do not have sufficient Privileges.
3. User Is Not Logged in with Service Account.
4. The configuration is done on Local Machine and Disconnected with the Domain Controller.

so, I had updated my credentials using STSADM with this command

stsadm -o updatefarmcredentials -userlogin <domainusername> -password <newpassword>

and all is set and configured properly.

you can also use following powershell comands to do the same 

Get-SPManagedAccount

New-SPManagedAccount

Remove-SPManagedAccount

Set-SPManagedAccount