You don't have to delete drivers, just update them... first try uninstalling the Network Adapter driver, restart the computer and it will be reinstalled automatically and correctly. If that doesn't work, try updating it with one already in your system, that's in the compatible drivers list.
Device Manager / Network Adapters / right click your adapter / Update driver software / Browse my computer for driver software / Let me pick from a list....... Compatible Driers List / Select the driver and press Next... the driver will be installed.
If the problem persists, you may need to install the Ethernet driver included in the motherboard drivers disk.
How to use Device Manager in Windows 7...