A colleague got some trouble connecting with the VMware Data Recovery appliance, received this warning:
Error: Could not connect to the Data Recovery on the appliance
Please make sure the Data Recovery appliance is powered on. If the problem persists, please restart the Data Recovery appliance

Time for some troubleshooting:
- Ping test was successful;
- Could resolve DNS names;
- Rebooted the appliance;
- No weird error in the event log;
Resolution:
After checking the appliance version (VMware Data Recovery 2.0.1131) and the Plugin-Version (VMware Data Recovery Plugin 1.1.37) I thought.. maybe I need to update the plugin

After upgrading the plugin to version 1.2.1.3 I was able to connect the appliance again:

Result:

More information: Troubleshooting VMware Data Recovery plug-in connection issues
This release of VMware vCenter Server 4.1 Update 1 offers the following improvements:
- Additional Guest Operating System Customization Support: vCenter Server now supports customization of the following guest operating systems:
- Windows 7 SP1 (x32 and x64)
- Windows Server 2008 R2 SP1 (x32 and x64)
- RHEL 6.0 (x32 and x64)
- RHEL5.5 (x32 and x64)
- Additional vCenter Server Database Support: vCenter Server now supports the following databases:
- Microsoft SQL Server 2008 R2
- Microsoft SQL Server 2005 SP3
- Oracle 11g Standard/Enterprise Release 2, 11.2.0.1.0 or later, (x32 and x64)
- IBM DB2 9.7.2 Express C (x32 and x64)
- IBM DB2 9.7.2 Enterprise (x32 and x64)
For more information about using IBM DB2 – 9.7.2 database with vCenter Server 4.1 Update 1, see KB 1033201.
- Resolved Issues: In addition, this release delivers a number of bug fixes that have been documented in the Resolved Issues
Download: VMware
Repair svchost.exe
- Boot your server/computer is Safe Mode
The Windows Taskbar disappeared so you can run CMD by pressing “Windows + R” or press “CTRL + ALT + DEL” and press CRL when you click on File > New Task (RUN).
Repair SVCHOST
- C:\ [ENTER]
- cd windows\$NTServicePackUninstall$ [ENTER]
- copy svchost.exe c:\windows\system32\ [ENTER]
svchost.exe will replaced, if not you can repair it by using the i386 folder:
- C:\
- cd i386 [ENTER]
- expand svchost.ex_ c:\windows\system32\svchost.exe [ENTER]
Mcafee Antivirus
Now you need to rollback to the latest DAT definition of the McAfee Framework:
Start -> Programs-> McAfee -> McAfee Console-> Tools-> DAT’s rollback–> Answer YES to confirm

More information about DAT 5958: NAI