The reason for it being unavailable in the first place may be the fact that your were using someone else's account. If your cousin is signed into steam, you won't be able to play. You should have mentioned that at the start. God know what you have done to steam/your system now.
My advice would be the full manual uninstallation as directed here:
You mentioned you can't use ste3am at all now so skip the bit about uninstalling the game on steam first.
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Completing a Full Uninstall:
This uninstall guide assumes earlier editions of Football Manager were and are still installed such as Football Manager 2010 or 2011.
If this is not the case please delete the Sports Interactive folder instead of the Football Manager 2012 folder as outlined in each individual step:
* Before proceeding please make sure to write down the username and password of your Steam account as you will need them to reinstall afterwards.
Start by uninstalling Football Manager 2012 through Steam:
Right-click on Football Manager 2012 and select “Delete Local Content…”
Next, delete Sports Interactive from my Documents:
Start Menu > Documents > Sports Interactive > Football Manager 2012
Delete Football Manager 2012 (This will delete save data, please store elsewhere such as the desktop if required).
Next confirm the removal the Football Manager 2012 Settings.
Confirm that hidden folders are enabled:
Step 1
- Click on the Start button,
- Click on the Control Panel,
- From the Control Panel Select Classic View,
- Once selected locate and double click on Folder Options.
- Click on the View tab.
Step 2
- Under the Hidden files and folders section select the radio button labelled Show hidden files and folders.
- Remove the checkmark from the checkbox labelled Hide extensions for known file types.
- Remove the checkmark from the checkbox labelled Hide protected operating system files.
- Press the Apply button and then the OK button and shutdown My Computer.
- Now Windows Vista is configured to show all hidden files.
Step 3:
Remove the cache files for Football Manager 2012 as detailed below:
Go here:
XP:
C:\Documents and Settings\<username>\Application Data\Sports Interactive\
Vista/Win7:
C:\Users\<username>\AppData\Roaming\Sports Interactive\
Delete the Sports Interactive folder.
Then you will have to manually remove Steam:
1. Exit Steam.
2. Navigate to your Steam directory. (Typically C:\Program Files\Steam or C:\Program Files\Valve\Steam)
3. Delete all of the contents of your Steam directory.
When complete, make sure the Steam and FM12 registry entries have been removed. While doing the following, please be aware that the Windows registry is a very sensitive part of Windows. Mistakes can render your system unstable so be VERY careful when making any changes.
* For FM 2012:
- Click Start then Run.
- At the prompt type: REGEDIT. The registry editor will open.
- Click the "+" next to HKEY_LOCAL_MACHINE.
- Click the "+" next to SOFTWARE.
*If you have a 64-bits Operating System go to: SOFTWARE\Wow6432Node
- Click the "+" next to Sports Interactive Ltd.
- Right-Click the Football Manager 2012 folder.
- Select Delete.
- Go back to HKEY_LOCAL_MACHINE\SOFTWARE.
- Click the "+" next to Microsoft
- Click the "+" next to Windows
- Click the "+" next to CurrentVersion
- Click the "+" next to Uninstall
- Right click & delete the key labelled:
- Football Manager fields
* For Steam:
In the left-hand column of your registry editor, navigate to: HKEY_CURRENT_USER\Software\Valve\Steam.
Right-click on Valve select Delete.
- For 32-bit operating systems:
In the left-hand column of your registry editor, navigate to: HKEY_LOCAL_MACHINE\SOFTWARE\Valve\.
Right-click on Valve and select Delete.
- For 64-bit operating systems:
In the left-hand column of your registry editor, navigate to: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Valve\.
Right-click on Valve and select Delete.
When completed please close the Registry Editor, restart your computer and try the installation again.
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