Access denied when adding people to SharePoint group

Question

Hi all,
     I've been having problems with my SharePoint 2010 deployment that wasn't deployed by me. Sound familiar? Anyways, here is my problem: I try to add people to a SharePoint group and I'm getting:
Access Denied.
You do not have permission to perform this action or access this resource.
Troubleshoot issues with Microsoft SharePoint Foundation.
Correlation ID: 930333d7-64dc-4135-8f51-686303a9847c
Date and Time: 7/29/2014 2:21:11 PM
I've been having problems with pulling AD members in one of my site collections for awhile now. Been troubleshooting with what information I can find online. One step I took was to blank out the LDAP search string for each site collection so that it's not
limited to certain OUs. 
Also I am getting security log entries that my farm account is trying to authenticate as a privileged [administrative permissioned] account for an employee that is no longer with us. Coincidentally enough he's the one that deployed this SharePoint solution
originally.
I need help in tracking down why I cannot add users to groups in this one site collection; but my root site collection I can add people no problem.
Environment:
Server1: SQL 2008 R2 on Windows Server 2008 R2
Server2: SharePoint 2010 with Enterprise CALs on Server 2008 R2
Current event viewer entries of note:
Load control template file /_controltemplates/TaxonomyPicker.ascx failed: Could not load the assembly ';Microsoft.SharePoint.Portal, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c'. Make sure that it is compiled before accessing the page.
Object Cache: The super user account utilized by the cache is not configured. This can increase the number of cache misses, which causes the page requests to consume unneccesary system resources.
To configure the account use the following command 'stsadm -o setproperty -propertyname portalsuperuseraccount -propertyvalue account -url webappurl'. The account should be any account that has Full Control access to the SharePoint databases but is not an application pool account.
Additional Data:
Current default super user account: SHAREPOINT\system
A logon was attempted using explicit credentials.
Subject:
Security ID: domain\farm_account
Account Name: farm_account
Account Domain: domain
Logon ID: 0x79c13
Logon GUID: {e25efc28-8db1-ea76-9a8e-6d0143a681d9}
Account Whose Credentials Were Used:
Account Name: former_admin_employee
Account Domain: domain
Logon GUID: {00000000-0000-0000-0000-000000000000}
Target Server:
Target Server Name: domain_controller.domain.net
Additional Information: domain_controller.domain.net
Process Information:
Process ID: 0x13b0
Process Name: C:\Windows\System32\inetsrv\w3wp.exe
Network Information:
Network Address: -
Port: -
This event is generated when a process attempts to log on an account by explicitly specifying that account’s credentials. This most commonly occurs in batch-type configurations such as scheduled tasks, or when using the RUNAS command.

Answer 1

Hello,
> he's the one that deployed this SharePoint solution originally.
Are you trying to add user by custom solution? If so then it seems your code is using the impersonate method to run code with admin privileged (i.e. RunWithElevatedPrivileges or User token).
If this is the case then you have to first add new account as site collection in site then change that web application pool identity on IIS. Go to IIS-->select your web app pool-->then  go to properties and  verify which account is been used
there. If it is old then replace with your account.
Let us know your result
Hemendra:Yesterday is just a memory,Tomorrow we may never see
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