All machines not yet reported

We have got computers that are reporting to the WSUS server but all are reporting not yet reported in the status. The computers fail the clientdebug test with the below error:

Checking Connection to WSUS/SUS Server
WUServer = http://fhqmgr001:8530
WUStatusServer = http://fhqmgr001:8530
UseWuServer is enabled. . . . . . . . . . . . . . . . . PASS
Connection to server. . . . . . . . . . . . . . . . . . PASS

WinHttpDownloadFileToMemory(szURLDest, NULL, 0, NULL, NULL, NULL,
&downloadBuffer) failed with hr=0x80072efd

A connection with the server could not be established.

I am able to ping the server and also can browse to the cab file. Can anyone help me please? Thanks.

Even we are not getting machines that are not connecting to the server with the below error:

Checking Connection to WSUS/SUS Server
WUServer = http://fhqmgr001:8530
WUStatusServer = http://fhqmgr001:8530
UseWuServer is enabled. . . . . . . . . . . . . . . . . PASS

VerifyWUServerURL() failed with hr=0x801901f6

Please help us. Thanks

Have you tried to bowse to the cab file using Internet Explorer or Windows Explorer? Have you tried to do this from a desktop logged into a domain admin account or a normal user account? It seems to me that the issue could be some incorrect permissions on the web server. You should configure the virtual server with Anonumous Access enabled and also all of the virtual direcotries except leaving the WSUSAdmin.

I did browse to the cab file from an ordinary user in IE, and i'm able to open the text file that is displayed.

I got a fix to this similar kind of problem that I was facing. The server that I was running an instance of SCCM and as such had a flasg set that told the clients not to report their status back to the WSUS server. I just found a tool which will update this flag even if SCCM is removed from the system.