Solved: windows 7 hp does not recognise headphones/microphones

Since (clean) installing Windows 7 Home Premium my computer does not recognise the headphones/microphone plugged in on the front panel connectors. I have sound on speakers which works from the connector at the back of the computer and equally I can get headphones if I plug them in at the back of the computer. I have installed new RealTek drivers and device manager tells me all is working. The audio trouble-shooter facility just tells me that the headphones/microphone is not plugged in. I am not a very experienced computer user so I have no idea what I should try next to get the sound to work from the front panel. Any help would be gratefully received! Thanks.

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 7 Home Premium, Service Pack 1, 32 bit
Processor: Intel(R) Core(TM)2 CPU 6300 @ 1.86GHz, x64 Family 6 Model 15 Stepping 6
Processor Count: 2
RAM: 1022 Mb
Graphics Card: NVIDIA GeForce 7300 SE/7200 GS, 64 Mb
Hard Drives: C: Total - 58635 MB, Free - 39218 MB; D: Total - 123342 MB, Free - 101027 MB;
Motherboard: Packard Bell BV, Cuba MS-7301
Antivirus: Norton Internet Security, Updated and Enabled