Hi I hope someone can help me. I have a regularly scheduled backup of my local disk to my USB-connected Passport drive. Until recently, it has worked great. However, now the backup fails consistently with erro 0x81000039. The error message is "Details: The semaphore timeout period has expired." I have run chkdsk on both drives, with no errors reported. Regards, Harold Ship

Please try the following steps on the Windows 7 computer to change the NTLM authentication level: 1. Click Start. Enter “gpedit.msc” in the Start Search box. 2. Locate to Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\ 3. In the right pane, double-click on “Network security: LAN Manager authentication level”. 4. Change the level to “Send LM & NTLM - use NTLMv2 session security if negotiated”. If the issue still occurs, I suggest you contact the drive manufacturer to refresh the firmware of the drive.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.