Hi,Software update scan cycle on XP clients is getting failed.In the ScanAgent.log is giving following error"Scan Failed for ToolUniqueID={C099C03E-309B-4280-A7B0-60F0A175170A}, with Error=0xc8000643"Could anyone tell me why this error is occuring?thanks in advance

See if %windir%\windowsupdate.log contains more information.

Hi TorstenSome synchronization error is reported in the log.Below is the log file.07:44:33:784 1124 ff4 Agent ** START ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:44:33:784 1124 ff4 Agent *********2010-02-04 07:44:33:784 1124 ff4 Agent * Include potentially superseded updates2010-02-04 07:44:33:784 1124 ff4 Agent * Online = Yes; Ignore download priority = Yes2010-02-04 07:44:33:784 1124 ff4 Agent * Criteria = "(DeploymentAction=* AND Type='Software') OR (DeploymentAction=* AND Type='Driver')"2010-02-04 07:44:33:784 1124 ff4 Agent * ServiceID = {3DA21691-E39D-4DA6-8A4B-B43877BCB1B7}2010-02-04 07:44:33:784 1328 b18 COMAPI <<-- SUBMITTED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:44:37:536 1124 ff4 PT +++++++++++ PT: Synchronizing server updates +++++++++++2010-02-04 07:44:37:552 1124 ff4 PT + ServiceId = {3DA21691-E39D-4DA6-8A4B-B43877BCB1B7}, Server URL = http://DCBSRV11.MYIT.COM:8530/ClientWebService/client.asmx2010-02-04 07:44:40:788 1124 ff4 PT WARNING: Cached cookie has expired or new PID is available2010-02-04 07:44:40:788 1124 ff4 PT Initializing simple targeting cookie, clientId = 8c97951d-b3a1-4d09-9a46-1b045e438e4a, target group = , DNS name = vm10129nzqzq.myit.com2010-02-04 07:44:40:788 1124 ff4 PT Server URL = http://DCBSRV11.MYIT.COM:8530/SimpleAuthWebService/SimpleAuth.asmx2010-02-04 07:46:01:944 1124 ff4 PT WARNING: PopulateDataStore failed: 0xc80006432010-02-04 07:46:01:944 1124 ff4 PT WARNING: Sync of Updates: 0xc80006432010-02-04 07:46:01:944 1124 ff4 PT WARNING: SyncServerUpdatesInternal failed: 0xc80006432010-02-04 07:46:01:944 1124 ff4 Agent * WARNING: Failed to synchronize, error = 0xC80006432010-02-04 07:46:01:991 1124 448 AU Can not perform non-interactive scan if AU is interactive-only2010-02-04 07:46:02:022 1124 ff4 Agent * WARNING: Exit code = 0xC80006432010-02-04 07:46:02:022 1124 ff4 Agent *********2010-02-04 07:46:02:022 1124 ff4 Agent ** END ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:46:02:022 1124 ff4 Agent *************2010-02-04 07:46:02:022 1124 ff4 Agent WARNING: WU client failed Searching for update with error 0xc80006432010-02-04 07:46:02:085 1328 b18 COMAPI >>-- RESUMED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:46:02:085 1328 b18 COMAPI - Updates found = 02010-02-04 07:46:02:085 1328 b18 COMAPI - WARNING: Exit code = 0x00000000, Result code = 0xC80006432010-02-04 07:46:02:085 1328 b18 COMAPI ---------2010-02-04 07:46:02:085 1328 b18 COMAPI -- END -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:46:02:085 1328 b18 COMAPI -------------2010-02-04 07:46:02:085 1328 b18 COMAPI WARNING: Operation failed due to earlier error, hr=C80006432010-02-04 07:46:02:085 1328 b18 COMAPI FATAL: Unable to complete asynchronous search. (hr=C8000643)2010-02-04 07:46:07:056 1124 ff4 Report REPORT EVENT: {0CBECABE-3CB2-4471-91A2-EAEA4E291963} 2010-02-04 07:46:02:022+0100 1 148 101 {00000000-0000-0000-0000-000000000000} 0 c8000643 CcmExec Failure Software Synchronization Windows Update Client failed to detect with error 0xc8000643.2010-02-04 07:50:22:174 1328 a18 COMAPI -------------2010-02-04 07:50:22:174 1328 a18 COMAPI -- START -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:22:174 1328 a18 COMAPI ---------2010-02-04 07:50:22:189 1124 ff4 Agent *************2010-02-04 07:50:22:189 1124 ff4 Agent ** START ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:50:22:189 1124 ff4 Agent *********2010-02-04 07:50:22:189 1124 ff4 Agent * Include potentially superseded updates2010-02-04 07:50:22:189 1124 ff4 Agent * Online = Yes; Ignore download priority = Yes2010-02-04 07:50:22:189 1124 ff4 Agent * Criteria = "(DeploymentAction=* AND Type='Software') OR (DeploymentAction=* AND Type='Driver')"2010-02-04 07:50:22:189 1328 a18 COMAPI <<-- SUBMITTED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:22:189 1124 ff4 Agent * ServiceID = {3DA21691-E39D-4DA6-8A4B-B43877BCB1B7}2010-02-04 07:50:22:611 1124 ff4 Agent * WARNING: Exit code = 0xC80006432010-02-04 07:50:22:611 1124 ff4 Agent *********2010-02-04 07:50:22:611 1124 ff4 Agent ** END ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:50:22:611 1124 ff4 Agent *************2010-02-04 07:50:22:611 1124 ff4 Agent WARNING: WU client failed Searching for update with error 0xc80006432010-02-04 07:50:22:627 1328 a18 COMAPI >>-- RESUMED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:22:627 1328 a18 COMAPI - Updates found = 02010-02-04 07:50:22:627 1328 a18 COMAPI - WARNING: Exit code = 0x00000000, Result code = 0xC80006432010-02-04 07:50:22:627 1328 a18 COMAPI ---------2010-02-04 07:50:22:627 1328 a18 COMAPI -- END -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:22:627 1328 a18 COMAPI -------------2010-02-04 07:50:22:627 1328 a18 COMAPI WARNING: Operation failed due to earlier error, hr=C80006432010-02-04 07:50:22:627 1328 a18 COMAPI FATAL: Unable to complete asynchronous search. (hr=C8000643)2010-02-04 07:50:24:799 1328 edc COMAPI -------------2010-02-04 07:50:24:799 1328 edc COMAPI -- START -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:24:799 1328 edc COMAPI ---------2010-02-04 07:50:24:799 1328 edc COMAPI <<-- SUBMITTED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:24:799 1124 ff4 Agent *************2010-02-04 07:50:24:799 1124 ff4 Agent ** START ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:50:24:799 1124 ff4 Agent *********2010-02-04 07:50:24:799 1124 ff4 Agent * Include potentially superseded updates2010-02-04 07:50:24:799 1124 ff4 Agent * Online = Yes; Ignore download priority = Yes2010-02-04 07:50:24:799 1124 ff4 Agent * Criteria = "(DeploymentAction=* AND Type='Software') OR (DeploymentAction=* AND Type='Driver')"2010-02-04 07:50:24:799 1124 ff4 Agent * ServiceID = {3DA21691-E39D-4DA6-8A4B-B43877BCB1B7}2010-02-04 07:50:24:987 1124 ff4 Agent * WARNING: Exit code = 0xC80006432010-02-04 07:50:24:987 1124 ff4 Agent *********2010-02-04 07:50:24:987 1124 ff4 Agent ** END ** Agent: Finding updates [CallerId = CcmExec]2010-02-04 07:50:24:987 1124 ff4 Agent *************2010-02-04 07:50:24:987 1124 ff4 Agent WARNING: WU client failed Searching for update with error 0xc80006432010-02-04 07:50:25:002 1328 edc COMAPI >>-- RESUMED -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:25:002 1328 edc COMAPI - Updates found = 02010-02-04 07:50:25:002 1328 edc COMAPI - WARNING: Exit code = 0x00000000, Result code = 0xC80006432010-02-04 07:50:25:002 1328 edc COMAPI ---------2010-02-04 07:50:25:002 1328 edc COMAPI -- END -- COMAPI: Search [ClientId = CcmExec]2010-02-04 07:50:25:002 1328 edc COMAPI -------------2010-02-04 07:50:25:002 1328 edc COMAPI WARNING: Operation failed due to earlier error, hr=C80006432010-02-04 07:50:25:002 1328 edc COMAPI FATAL: Unable to complete asynchronous search. (hr=C8000643)2010-02-04 07:50:27:612 1124 ff4 Report REPORT EVENT: {BE770F37-B945-4717-884A-411E4C963308} 2010-02-04 07:50:22:611+0100 1 148 101 {00000000-0000-0000-0000-000000000000} 0 c8000643 CcmExec Failure Software Synchronization Windows Update Client failed to detect with error 0xc8000643.2010-02-04 07:50:27:612 1124 ff4 Report REPORT EVENT: {4837AD0E-2B51-4384-8089-EDD9E438917F} 2010-02-04 07:50:24:987+0100 1 148 101 {00000000-0000-0000-0000-000000000000} 0 c8000643 CcmExec Failure Software Synchronization Windows Update Client failed to detect with error 0xc8000643.2010-02-04 08:29:05:463 1328 f64 COMAPI -------------

Just restarting the service does not make too much sense. The second command just renames the SoftwareDistribution folder. You can stop the service manually, rename or delete the folder and restart the service again.

Hi Torsten,I have manually stoped the service then named the folder then againg restarted the service.Still its not working.