在编程语言中，可以使用内置的Base64解码函数或库来解码Base64字符串。以下是一些常见编程语言的解决方案示例：

Python:

import base64

encoded_string = "QmFzZTY0JiM4MjQmZGVzY3JpcHRpb24gbWV0aG9kIOKAnE3igJMgdmFsaWRhdGlvbiEK"
try:
    decoded_string = base64.b64decode(encoded_string).decode('utf-8')
    print(decoded_string)
except Exception as e:
    print("解码错误：", str(e))

Java:

import java.util.Base64;
import java.nio.charset.StandardCharsets;

String encodedString = "QmFzZTY0JiM4MjQmZGVzY3JpcHRpb24gbWV0aG9kIOKAnE3igJMgdmFsaWRhdGlvbiEK";
try {
    byte[] decodedBytes = Base64.getDecoder().decode(encodedString);
    String decodedString = new String(decodedBytes, StandardCharsets.UTF_8);
    System.out.println(decodedString);
} catch (Exception e) {
    System.out.println("解码错误：" + e.getMessage());
}

C#:

using System;

string encodedString = "QmFzZTY0JiM4MjQmZGVzY3JpcHRpb24gbWV0aG9kIOKAnE3igJMgdmFsaWRhdGlvbiEK";
try
{
    byte[] data = Convert.FromBase64String(encodedString);
    string decodedString = System.Text.Encoding.UTF8.GetString(data);
    Console.WriteLine(decodedString);
}
catch (Exception e)
{
    Console.WriteLine("解码错误：" + e.Message);
}

这些示例代码将尝试将给定的Base64字符串解码为原始字符串，并在解码错误时捕获异常并打印错误消息。请注意，如果Base64字符串无效或被篡改，解码过程可能会失败。