Issue: SharePoint 2010 User Profile Sync Service won't start. As many are already pulling their hair over the UPA Sync service issues, one of the errors and resolution is as below.
Error:-
02/22/2012 11:49:18.87 OWSTIMER.EXE 
(0x1A10) 0x0AE8 SharePoint Portal Server User Profiles g4wt High 
UpdateILMMA: Failed to update 
password. Exception: {1}..  Available parameters: 
Microsoft.ResourceManagement.WebServices.Client.PermissionDeniedException: 
Access to the requested resource(s) is denied     at 
Microsoft.ResourceManagement.WebServices.Client.ResourceTemplate.GetResource(UniqueIdentifier 
identifier, String[] attributeNames, Nullable`1 resourceTime)     at 
Microsoft.ResourceManagement.WebServices.ResourceManager..ctor(UniqueIdentifier 
resourceIdentifier, String typeName, String[] attributeNames, CultureInfo 
locale, Boolean includePermissionHints, TimeZoneInfo localTimeZone)     at 
Microsoft.ResourceManagement.WebServices.ResourceManager..ctor(UniqueIdentifier 
resourceIdentifier, String typeName, String[] attributeNames, CultureInfo 
locale, Boolean includePermissionHints)     at 
Microsoft.Office.Server.UserProfiles.Synchronization.MAConfiguration..ctor(Guid 
resourceIdentifier)     at 
Microsoft.Office.Server.UserProfiles.Synchronization.ILMMAConfiguration..ctor(Guid 
resourceIdentifier)     at 
Microsoft.Office.Server.UserProfiles.UserProfileConfigManager.UpdateILMMA(String 
databaseServerIlm, String databaseInstanceIlm, String databaseName, String 
domain, String userName, SecureString password) . 
a4398ace-cf1f-4a23-a976-830806ce4c67
02/22/2012 
11:49:18.87 OWSTIMER.EXE (0x1A10) 0x0AE8 SharePoint Portal Server User Profiles 
9q17 High UserProfileApplication.SynchronizeMIIS: Failed to configure ILM MA, will attempt 
during next rerun. Exception: 
Microsoft.ResourceManagement.WebServices.Client.PermissionDeniedException: 
Access to the requested resource(s) is denied     at 
Microsoft.ResourceManagement.WebServices.Client.ResourceTemplate.GetResource(UniqueIdentifier 
identifier, String[] attributeNames, Nullable`1 resourceTime)     at 
Microsoft.ResourceManagement.WebServices.ResourceManager..ctor(UniqueIdentifier 
resourceIdentifier, String typeName, String[] attributeNames, CultureInfo 
locale, Boolean includePermissionHints, TimeZoneInfo localTimeZone)     at 
Microsoft.ResourceManagement.WebServices.ResourceManager..ctor(UniqueIdentifier 
resourceIdentifier, String typeName, String[] attributeNames, CultureInfo 
locale, Boolean includePermissionHints)     at 
Microsoft.Office.Server.UserProfiles.Synchronization.MAConfiguration..ctor(Guid 
resourceIdentifier)     at 
Microsoft.Office.Server.UserProfiles.Synchronization.ILMMAConfiguration..ctor(Guid 
resourceIdentifier)     at 
Microsoft.Office.Server.UserProfiles.UserProfileConfigManager.UpdateILMMA(String 
databaseServerIlm, String databaseInstanceIlm, String databaseName, String 
domain, String userName, SecureString password)     at 
Microsoft.Office.Server.Administration.UserProfileApplication.SetupSynchronizationService(ProfileSynchronizationServiceInstance 
profileSyncInstance). a4398ace-cf1f-4a23-a976-830806ce4c67
02/22/2012 
11:49:18.87 OWSTIMER.EXE (0x1A10) 0x0AE8 SharePoint Portal Server User Profiles 
9i1u Medium UserProfileApplication.SynchronizeMIIS: End setup for 
'UserProfileServiceApplication'. 
a4398ace-cf1f-4a23-a976-830806ce4c67
Log Name:      Application
Source:     
   FIMSynchronizationService
Date:       
   2/22/2012 11:49:18 AM
Event ID:   
   6331
Task 
Category: MA Extension
Level:       
  Error
Keywords:   
   Classic
User:       
   N/A
Computer: computer.domain.com
Description:
A update on 
the configuration of a MA or MV failed to replicate to a target connector 
directory that is capable  of storing MA/MV configurations.  As a result, the 
MA/MV configuration data in this connector directory is not up to date.  Please 
correct the condition that causes the error, and triggers a resync by 
updating the password 
information of the target MA. 
Additional 
information: 
Error Code: 
0x80231317 
Error 
Message: (The management agent 
failed to validate against the application store with the specified 
credentials.) 
Operation: 
Clean up MAs 
Name of the 
MA to replicate:  
Name of the 
target MA: ILMMA 
Guid of the 
target MA: {F2CD610F-9L7E1-45S2-834J-D76734328DFCAC4}
  
 (The management 
agent failed to validate against the application store with the specified 
credentials.)
Clean up MAs
Resolution:- 
1. Make sure you are logged into the Server as the UPA Service account.
2. Run RSOP information for account specifically for 
'Allow Logon Locally' and 'Deny Logon Locally' GPO.
3. If the User Account is part of any AD group and that Group is added to the "Deny Logon Locally" policy, the UPA Sync service will NOT start.
4. The Service account has to be specifically be part of the "Allow Logon Locally" GPO.