AWS Lightsail中Plesk部署的FTP站点无法在IE中连接

Hey there! Let's break down why IE is refusing to connect to your FTP site when other browsers and clients work just fine—IE has always had some quirky FTP behavior, so let's go through the most likely fixes:

1. Check IE's Passive FTP Mode Setting #

IE defaults to active FTP in some versions, which can fail if your Lightsail instance is behind NAT (which it is). Active FTP requires the server to initiate a connection back to your local machine, which firewalls often block. Here's how to switch to passive mode:

• Open IE, go to Tools > Internet Options > Advanced tab
• Scroll down to the "Browsing" section
• Make sure the box for "Use passive FTP (for firewall and DSL modem compatibility)" is checked
• Click Apply and restart IE, then test the FTP connection again

2. Force Anonymous Credentials in IE's Address Bar #

Sometimes IE doesn't automatically send anonymous credentials correctly. Try explicitly specifying them in the URL:

• Instead of just ftp://yourdomain.com, use ftp://anonymous:your-email@yourdomain.com
  (Replace your-email with any valid email address—anonymous FTP typically accepts any email as a password)

3. Disable IE Enhanced Security Configuration (IE ESC) #

Windows Server 2012 R2 enables IE ESC by default, which blocks access to untrusted sites (including your FTP server). To turn it off:

• Open Server Manager from the taskbar
• Go to Local Server in the left pane
• Look for the "IE Enhanced Security Configuration" option (it'll say "On" by default)
• Click the link, set both Administrators and Users to Off
• Click OK, then restart IE and test

4. Verify IE's Proxy Settings #

If IE is using a proxy server, it might be routing FTP traffic incorrectly:

• Go to Tools > Internet Options > Connections > LAN Settings
• Uncheck "Use a proxy server for your LAN" (if it's enabled)
• If you need to keep the proxy, add your FTP domain to the "Exceptions" list (separate with semicolons if multiple)
• Save changes and test again

5. Check Plesk/IIS FTP Server Compatibility Settings #

Since you're using Plesk, it's likely running IIS FTP under the hood. Double-check these settings:

• Log into Plesk, go to your domain's FTP Access settings
• Ensure "UTF-8 support" is enabled (IE can struggle with non-UTF8 FTP servers)
• Verify that both anonymous and user-based authentication are correctly configured (you said they work in other clients, but sometimes IE has stricter checks)
• If you're using IIS directly (outside Plesk), confirm the FTP site's Firewall Support settings are configured to use your Lightsail instance's public IP (this helps with passive mode port mapping)

If none of these fix it, try clearing IE's cache and cookies (Tools > Internet Options > Delete) or testing with a different user account on your local machine to rule out profile-specific issues.

内容的提问来源于stack exchange，提问作者IT researcher