#include<stdio.h>
char char1;
char char2;
int main()
{
char1='*';
char2="*****";
printf("c%\n",char2);
printf("c%\n",char1);
printf("c%\n",char1);
printf("c%\n",char2);
printf("c%\n",char1);
printf("c%\n",char1);
printf("c%\n",char2);
return(0);
}
/*用*写一个高7行，宽5行的字母E*/

你的char2是字符数组，不能给它赋字符串进去，所以错误……

笔误，char2是字符变量……我怎么说成数组了，……汗……

自己找一下错误吧！
#include<stdio.h>
int main()
{
char char1='*';
char char2[20]="*****";
printf("%s\n",char2);
printf("%c\n",char1);
printf("%c\n",char1);
printf("%s\n",char2);
printf("%c\n",char1);
printf("%c\n",char1);
printf("%s\n",char2);
return(0);
}

printf("c%\n",char2);
printf("c%\n",char1);
printf("c%\n",char1);
printf("c%\n",char2);
printf("c%\n",char1);
printf("c%\n",char1);
printf("c%\n",char2);/*1到7行改为printf("%c\n",char1),记住%在前面啊

应这样改
#include<stdio.h>
char char1[]="*";
char char2[]="*****";
int main()
{
printf("%s\n",char2);
printf("%s\n",char1);
printf("%s\n",char1);
printf("%s\n",char2);
printf("%s\n",char1);
printf("%s\n",char1);
printf("%s\n",char2);
//return(0);
return(0);
}

一个字符变量只能存储一个字符，再一个，输出的格式符%在前面不在后面！第二个声明一个字符数组，并赋值给字符数值！还有输出字符串的格式符是%s，输出字符的是%c！

错的很明显嘛，char2应该定义为数组

学习了！楼上正解！