This error can occur when connecting to an FTPS server and files are being uploaded or downloaded or a list of files is being retrieved.
This issue must be fixed on the Windows computer that is running the FTPS server:
- Run the Group Policy Editor (gpedit.msc)
- Go to Local Computer Policy --> Administrative Templates --> Network --> SSL Configuration Settings
- Move TLS_RSA_WITH_RC4_128_SHA to the top of the priority list. How to modify this setting:
- Open a blank notepad document.
- Copy and paste the list of available suites into it.
- Arrange the suites in the correct order; remove any suites you don't want to use.
- Place a comma at the end of every suite name except the last. Make sure there are NO embedded spaces.
- Remove all the line breaks so that the cipher suite names are on a single, long line.
- Copy the cipher-suite line to the clipboard, and then paste it into the edit box. The maximum length is 1023 characters.
- Enable TLS 1.1 and/or TLS 1.2 on servers running Windows 7 or Windows Server 2008 R2. Refer to Microsoft Knowledge Base Article 2588513 to use the automated Microsoft Fix it solution to enable or disable this workaround for TLS 1.1.
- Reboot Windows. This is important.