python - pip 安装后总出现版本无法满足的提示

之前自己的PIP崩溃了。所以重装Python2.7.11(Windows7 64bit），升级了PIP（8.1.1），也安装了所有的之前用过的库。但是最近发现，无论采用PIP安装任何库，只要是新的库，都会提示同样的错误：

C:\Python27\Lib\site-packages>pip install sqlmap
Collecting sqlmap
  Could not find a version that satisfies the requirement sqlmap (from versions: )
No matching distribution found for sqlmap

C:\Python27\Lib\site-packages>pip install sqlmap -i http://pypi.douban.com/simple/
Collecting sqlmap
  The repository located at pypi.douban.com is not a trusted or secure host and is being ignored. If this repository is
available via HTTPS it is recommended to use HTTPS instead, otherwise you may silence this warning and allow it anyways
with '--trusted-host pypi.douban.com'.
  Could not find a version that satisfies the requirement sqlmap (from versions: )
No matching distribution found for sqlmap

C:\Python27\Lib\site-packages>pip install wxPython
Collecting wxPython
  Could not find a version that satisfies the requirement wxPython (from versions: )
No matching distribution found for wxPython

C:\Python27\Lib\site-packages>pip install pyQt
Collecting pyQt
  Could not find a version that satisfies the requirement pyQt (from versions: )
No matching distribution found for pyQt

不知道是否因为自己是64位Python的原因？是否需要用virtualenv安装32位Python？