Powershell Sharepoint package not working

I have a problem with the SP PowerShell plugin.

First I ran:

Get-PSSnapin

to make sure it's not loaded yet. So I ran:

Add-PSSnapin Microsoft.SharePoint.PowerShell

This gave me the following error:

Add-PSSnapin: The Microsoft.SharePoint.PowerShell Windows PowerShell snap-in is not installed on this computer. By line: 1 char: 1 + Add-PSSnapin Microsoft.SharePoint.PowerShell + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~ + CategoryInfo: InvalidArgument: (Microsoft.SharePoint.PowerShell: String) [Add-PSSnapin], PSArgumentException + FullyQualifiedErrorId: AddPSSnapInRead, Microsoft.PowerShell.Commands.AddPSSnapinCommand

So basically I found a solution to run:

C: \ Windows \ Microsoft.NET \ Framework64 \ v4.0.30319 \ InstallUtil / LogToConsole = TRUE C: \ Windows \ assembly \ GAC_MSIL \ Microsoft.SharePoint.PowerShell \ 14.0.0.0__71e9bce111e9429c \ Microsoft.SharePoint.Powershell.dll

This in turn gives me an error:

An exception occurred during installation initialization: System.IO.FileNotFoundException: Could not load file or assembly "File: /// C: \ Windows \ Microsoft.NET \ assembly \ GAC_MSIL \ Microsoft.ShareP oint.PowerShell \ v4.0_15.0.0. 0__71e9bce111e9429c \ Microsoft.SharePoint.Powershell.dll "or one of its dependencies. The system cannot find the file specified.

Can anyone tell me what I am doing wrong or provide me with a solution?

Thank!