Invoke-WebRequest报403 Forbidden：手动可下载脚本无法实现求助

常见原因及对应解决办法 #

• 服务器验证请求来源：部分服务器会拦截非浏览器发起的请求，可添加模拟浏览器的请求头绕过验证：

  $cuser = (Get-WmiObject -Class Win32_ComputerSystem).UserName
  $source = "https://xxx/$cuser.txt"
  $destination = "C:\yyyy\$cuser.txt"
  $headers = @{
      "User-Agent" = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36"
  }
  Invoke-WebRequest -Uri $source -OutFile $destination -Headers $headers
  

• 用户名格式不符：Get-WmiObject Win32_ComputerSystem返回的用户名格式是DOMAIN\username，若服务器文件仅用纯用户名命名，需提取用户名部分：

  $cuser = (Get-WmiObject -Class Win32_ComputerSystem).UserName.Split('\')[-1]
  $source = "https://xxx/$cuser.txt"
  $destination = "C:\yyyy\$cuser.txt"
  Invoke-WebRequest -Uri $source -OutFile $destination
  

• 缺少会话Cookie：手动下载时浏览器会携带登录会话Cookie，脚本默认无该信息，可导出浏览器对应站点的Cookie添加到请求头：

  $cuser = (Get-WmiObject -Class Win32_ComputerSystem).UserName
  $source = "https://xxx/$cuser.txt"
  $destination = "C:\yyyy\$cuser.txt"
  $headers = @{
      "Cookie" = "替换为浏览器导出的Cookie内容"
  }
  Invoke-WebRequest -Uri $source -OutFile $destination -Headers $headers
  

• 调整请求参数：尝试添加-UseBasicParsing参数或切换到Invoke-RestMethod：

  $cuser = (Get-WmiObject -Class Win32_ComputerSystem).UserName
  $source = "https://xxx/$cuser.txt"
  $destination = "C:\yyyy\$cuser.txt"
  Invoke-RestMethod -Uri $source -OutFile $destination -UseBasicParsing
  

内容的提问来源于stack exchange，提问作者Marco Gentilesca