Workspace error

When I go to the web occurs to me this error. 
User is the domain admin.  Created in IIS  full domain name, but still does not work.

Initialization failed: Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: indexAn error has occurred.
Please contact your administrator.
Error:
Initialization failed before PreInit: Thread was being aborted.
Possible causes
- using anonymous logon in IIS while Windows security is specified in Workspace configuration
- current logged on user can not be verified against the Active Directory Membership provider
- please review log files for more information

Answers:

Following could be the condition

1. check if other users are able to access

if Yes then check for duplicate in workspace.userprofile table using below query
"
SELECT  userid
  FROM [K2].[Workspace].[UserProfile]

 group by userd having count(*) > 1
"

duplicate then remove one of them from the userprofile table and Bingo!!!!

2. Else
Open the workspace web.config file, search for Ldap you shoud see this LDAP://[domain]). At the end of the .com of the domain add :389 The correct string should look like this “LDAP://[domain]:389” Do an IIS reset and workspace should work.