I try to connect to a SBS2011 server using WebDAV, but cannot open any Office files. When I try to copy them first to my local system it works fine. Opening PDF and TXT files works fine as well.

We have four other servers (SBS2011 and 2008R2) hosting WebDAV solutions, but no problem there.

I think it has something to do with the security, because Wireshark is mentioning security level warnings. But it isn't clear to me what's going on.

I tried to change the registry of my client to enable Basic authentication. But that doesn't work either. When I use a third party tool like Cloudsafe then it works fine, but unfortunately that's no option here.

I hope to find the solution on server side, somebody with tips?

Thx in advanced.

• Edited by Guido Knote Monday, March 23, 2015 4:08 PM

Hi,

Since the files can be opened on local, basically these files are actually fine.

Based on the error message, usually this issue is caused by malware on the affected machine.

In order to clean your machine, run Microsoft Safety Scanner (http://www.microsoft.com/security/scanner/en-us/default.aspx). If infected, Safety Scanner should clean the virus from the system, however it will not repair corrupted files. You will still need to restore those from a backup. A detailed analysis of affected files submitted to Microsoft for investigation has revealed the files are encrypted with a private and public key. The files cannot be recovered without the private key, which is more than likely held by the attacker. The premise of ransomware is such that if a person pays the ransom the key is provided to "unlock" the files.

As this issue only occurs with one of your servers, and you have got the security warnings, I agree with you that this may need to be resolved on the server side. For more information, you can post the question in the Windows Small Business Server forum:

https://social.technet.microsoft.com/Forums/en-US/home?category=sbsserver

Regards,

Melon Chen
TechNet Community Su

Hi Melon,

Thx for your reaction. Malware is not the problem. We tried to connect from many different systems and they all have the same problem. Yesterday I discovered Fiddler and with Fiddler the problem disappeared, just like CloudSafe did. 

It seems that 3rd party software solves connection and/or security issues, but I need to know the cause, so I can fix the server.