for the last 12 months I have been able to connect to my work PC uscing RDC. This abiity has suddenly stopped and everything I read says its not available on Home Premium 7. Is there a fix/patch for this problem?

What you read is true, but I think you're misunderstanding it. Windows 7 Home Premium cannot serve as an RDC host, meaning other PCs can't connect to it. It can, however, work as an RDC client, meaning it can connect to other computers that are acting as hosts (ie. XP Pro, Vista Business and Ultimate, Windows 7 Pro and Ultimate, Windows 2000 Server and above...) What OS is your work PC running? It sounds more like there's a network connectivity issue at play here; has anyone installed new security software on any of the PCs or network?