SFC /SCANNOW: RPC server is unavailable

Not sure what's happened, but an old machine that we use for accounts has worked for years. There's no real updates for Windows XP anymore, so nothing should have changed. We don't use it for anything else, so in theory it should be fine, but it's gone weird: It will no longer boot in anything but Safe Mode.

So while in Safe Mode I've tried to run SFC /SCANNOW (and SFC /SCANONCE) to see if there's been any corruption with the system files, but when I try I get the following error:

Windows File Protection could not make the requested change.

The specific error code is 0x000006ba [The RPC server is unavailable.]

• I've checked services.msc and the Remote Procedure Call (RPC) service is running.
• I've checked that Windows File Protection (WFP) is enabled. (The registry and SFCDisable is set to 0.)
• I've made sure that File and Printer Sharing and Internet Protocol (TCP/IP) are installed and running
• I've disabled the firewall and tried again
• I've run a virus scan and it found nothing

What's going on?

I know it's an ancient operating system, but we're stuck due to our equally aging software.

Another thing: While Chrome can load all sites perfectly, Internet Explorer cannot connect to Windows Update, or other websites. I've reset all options in that browser, but still it can't connect (even though, as I say, Chrome can). Seems like there might be some sort of connectivity issue somewhere?

What nobody will tell you is that you cannot run SFC in Safe Mode (no matter what services.msc tells you, the RPC server is NOT running).

This is why we can't run it. Argh!