Python version 2.7 required, which was not found in the registry

安装PIL库的时候，直接提示

Python version 2.7 required, which was not found in the registry

如图：

大意是说找不到注册表，网上搜索解决方案。

新建一个register.py文件写入代码：

import sys
  
from _winreg import *
  
# tweak as necessary
version = sys.version[:3]
installpath = sys.prefix
  
regpath = "SOFTWARE\\Python\\Pythoncore\\%s\\" % (version)
installkey = "InstallPath"
pythonkey = "PythonPath"
pythonpath = "%s;%s\\Lib\\;%s\\DLLs\\" % (
    installpath, installpath, installpath
)
  
def RegisterPy():
  try:
    reg = OpenKey(HKEY_CURRENT_USER, regpath)

  except EnvironmentError as e:
    try:
      reg = CreateKey(HKEY_CURRENT_USER, regpath)
      SetValue(reg, installkey, REG_SZ, installpath)
      SetValue(reg, pythonkey, REG_SZ, pythonpath)
      CloseKey(reg)
    except:
      print "*** Unable to register!"
      return
    print "--- Python", version, "is now registered!"
    return

  if (QueryValue(reg, installkey) == installpath and
    QueryValue(reg, pythonkey) == pythonpath):
    CloseKey(reg)
    print "=== Python", version, "is already registered!"
    return

  CloseKey(reg)

  print "*** Unable to register!"
  print "*** You probably have another Python installation!"

启动命令切到register.py文件目录下执行

$ python register.py
--- Python 2.7 is now is now registered!

重新安装PIL，错误解决，安装成功。

如果是Win7 64位的用户在安装Python 32位程序时，如果选择只为当前用户，以上问题不会出现。如果选择所有用户，就试着使用以上方法解决。

提示其它版本解决方法类似。