@SamsungASUS:
>Here< is a link to the requested Win7 driver, but I don't know whether it works or not.
Tip: If you are searching for a driver, you should mention the exact OS Edition. 32bit drivers don't work with a 64bit OS and 64bit drivers are not compatible with a 32bit OS.

@MeatWar:
Your links were ok, but the driver name indicates, that Win7 is not supported (despite the words "os=windows-7" within the links).

@SamsungASUS:
The only Marvell AVASTAR Family Wireless Network adapter drivers for Win7 I could find are attached.
Although the HardwareIDs do not match your specific Marvell device, the driver may work. If you want to test it, you have to force the installation by using the "Have Disk" button.
Good luck!

@SamsungASUS:
I generally do not modify drivers on request.
When you want to force the installation of a driver, which natively doesn't support the HardwareIDs of your device, you have to do the following:
1. Right-click onto the missing driver device.
2. Choose the options "Update driver" > "Browse my computer..." > "Let me pick..."
3. Click onto the "Have Disk" button, navigate to the driver folder and click onto the matching INF file (here: mwls87w7.inf).
4. Choose any of the listed Network adapters.
5. Disregard the warning you will get and let the driver be installed.
After the next reboot you will see, whether the device works or not.

@SamsungASUS:
That is a pity.
Why didn't you set a "Restorepoint" before starting the installation of a natively not matching driver?
This should always be done before doing something, which may not work.
By the way - your test result verifies, that the driver itself (= the *.sys file) doesn't work with your specific system. A modification of the *.inf file wouldn't solve the problem.
My tip: Ask the Marvell Support for a solution.