This started happening after the recent patches from Microsoft. It happens on 2 machines (both 32 & 64 bit) that backup was scheduled and working weekly for months. This is one error message that looks suspicious: The backup was not successful. The error is: Windows Backup failed to write the file: '<backup location>\WindowsImageBackup\<Computer Name>\MediaId'. (0x80780122). Also, this: The backup operation that started at '‎2010‎-‎10‎-‎05T04:27:33.656390900Z' has failed with following error code '2155348258' (Windows Backup failed to write the file: '<backup location>\WindowsImageBackup\<Computer Name>\MediaId'.). Please review the event details for a solution, and then rerun the backup operation once the issue is resolved. Finally, an error message that is not correct. User 'Fred' has read/write privs to the entire drive. I wrote files to each directory and erased them to make certain: The backup operation that started at '‎2010‎-‎10‎-‎05T04:27:33.656390900Z' has failed because the remote shared folder '\\DISKSTATION\Users\Fred-PC' that you are using for a backup storage location is not writeable. Please make sure user 'Fred' has write permissions for this location, and then rerun the backup operation. Again, this just started happening after both machines were backing up happily for months.

Hi, Thanks for posting in Microsoft TechNet forums. As I understand that you encounter the following scenario: 1. Backup failure with error: Windows Backup failed to write the file: '<backup location>\WindowsImageBackup\<Computer Name>\MediaId'. (0x80780122). 2. After you wrote files to each directory to erase them makes this error: the remote shared folder '\\DISKSTATION\Users\Fred-PC' that you are using for a backup storage location is not writeable. Here are my suggestions: Please do not wrote the files to each directory firstly. For the first error, do you backup in some external drive? The failure is about writing Mediaid.ini file, please do the following as administrator to rebuilding it: (refer to: http://www.vistax64.com/vista-file-management/184885-procedure-rebuild-mediaid-bin-restoring-backups.html ) (Sdutil is an internal tool, please ask customer contact Microsoft support to get this tool) 1.Unzip the sdutil.zip file and rename it from sdutil.ex_ to sdutil.exe 2.Copy the sdutil.exe to the root of the driver which contains the backup files 3.Open the folder Catalogs located bellow the folder BackupSet “aaaammdd” “xxxxxx” 4.Copy the file GlobalCatalog.wbcat to the root of this HD 5.Go to Start -> Execute and type CMD.exe 6.At this “DOS” window type: sdutil mediaid GlobalCatalog.wbcat [HD letter (as an example D:\)] 7.A new MediaID.bin is created 8.Try to restore the backup as usual using the advanced restore option and next the option restore an older backup created in this machine 9.If done: it’s over! 10.If it fails: Map a network driver at your LAN 11.Copy the MediaId.bin file to the root of the previous mapped LAN driver 12.Copy the whole folder BackupSet “aaaammdd” “xxxxxx” to this same driver 13.Try to restore the backup as usual using the advanced restore option and next the option restore backup created in another machine 14.At the next menu, point the backup folder at your LAN mapped driver and start the restore process After the above, please check if it works. Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information. Best Regards, Miya Yao TechNet Subscriber Support in forum. If you have any feedback on our support, please contact tngfb@microsoft.com This posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hello, I was not clear it seems. When I saw the error, 'access denied', I tested by copying files to the folder then deleted the test files. I do not normally even look into the folders as it has ran fine for months. So, to me, it seems that Windows 7 Backup suddenly lost the ability to write to a network device. This happens on 2 different machines. One is 32 bit, the other 64 bit. One runs Microsoft Security Essentials, the other has no anti-malware as it does not connect to the Internet. All other apps and tools are able to write to the device, Windows 7 Backup just lost the ability this week. Last week's backup ran normally on both machines, this week both are unable and fail in the same way. Please re-read the original post for details. This is not a restore issue, it is writing the backup.

Hi, Sorry for misunderstanding of the former post. I’m wondering whether the network device server is Windows or Linux, if Linux, please let us know which journaling file system are using, because upgraded from ext3 to ext4 may cause the permission issue. Meanwhile, please check the application log for errors after failure. Event viewer – Applications and Services Logs – Microsoft – Windows - Backup. You can sort the events in this log, or create a custom view for all Windows Backup events. Also check backup log. It’s in %windir%\logs\WindowsBackup. The primary useful log is the skipped files log, saved as: Backup Files 000-00-00000000_error.log. This file is removed at the end of the backup job if there were no skipped files or skipped volume. Regards, Miya Yao TechNet Subscriber Support in forum. If you have any feedback on our support, please contact tngfb@microsoft.com This posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi, Yes, the NAS is linux based and uses ext4. Any suggestions?

Is it Synology? If so, I’m afraid it could be a known issue, please refer to http://forum.synology.com/enu/viewtopic.php?f=159&t=28521 . Please contact the Synology support, they could have a patch to resolve this problem. Regards, Miya TechNet Subscriber Support in forum. If you have any feedback on our support, please contact tngfb@microsoft.com This posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

That is it. I have contacted them and they do have a patch for it. Thank you for the prompt, accurate advice! I appreciate it.

Problem with Synology systems is solved by DSM version 3.0-1354 (e.g. for DS1010+: http://www.synology.com/enu/support/releaseNote/DS1010+.php). Tested today's morning and works fine. Petr

Thank you. I will get the update.

Is it Synology? If so, I’m afraid it could be a known issue, please refer to http://forum.synology.com/enu/viewtopic.php?f=159&t=28521 . Please contact the Synology support, they could have a patch to resolve this problem. Regards, Miya TechNet Subscriber Support in forum. If you have any feedback on our support, please contact tngfb@microsoft.com This posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread. Hello there, Thanks for the tip! I was having the exact same issue. Just installed the DSM update, and everything is working! Thanks Gary

Hi Gary, Glad to hear you find the solution here. Welcome to ask any Windows 7-related questions in this forum. Regards, MiyaThis posting is provided "AS IS" with no warranties, and confers no rights. | Please remember to click "Mark as Answer" on the post that helps you, and to click "Unmark as Answer" if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.