SBS2003 backup failures

Hello,

I am using SBS2003 with SP2 and my my failes backup start failing through
NTBACKUP and start showing the following system error:

Event id 10021,Event Source:-DCOM
The launch and activation security descriptor for the COM Server application
with CLSID
{56BE716B-2F76-4DFA-8702-67AE10044F0B}
is invalid. It contains Access Control Entries with permissions that are
invalid. The requested action was therefore not performed. This security
permission can be corrected using the Component Services administrative tool.

and also in application warning:
Event id 4354, Event Source: EventSystem
The COM+ Event System failed to fire the RequestWriterInfo method on
subscription
{98A4C6E0-5FDF-4CD8-804A-2A5BD931EA54}-{00000000-0000-0000-0000-000000000000}-{00000000-0000-0000-0000-000000000000}.
The subscriber returned HRESULT 8002801D.

And error:
Event id 8019,Event Source:NTBackup
End Operation: Warnings or errors were encountered.
Consult the backup report for more details.

Nex warning:
Event id 1524,Event Source:Userenv
Windows cannot unload your classes registry file - it is still in use by
other applications or services. The file will be unloaded when it is no
longer in use.

Next eror:
Event id 5634,Event Source:SmallBusinessServer
One or more components of Small Business Server Backup failed. For more
information, click Backup in Server Management, and view the log files.

And:
Event id 6013,Event Source:VSS
Sqllib error: OLEDB Error encountered calling IDBInitialize::Initialize. hr
= 0x80004005. SQLSTATE: 08001, Native Error: 18
Error state: 1, Severity: 16
Source: Microsoft OLE DB Provider for SQL Server
Error message: [DBNETLIB][ConnectionOpen (SECDoClientHandshake()).]SSL
Security error.

Please help me fix these errors, because ntbackup is not working.
Thanks for any help.

Rasa