installing most recent stealth change causes PYTHON_EGG_CACHE problem

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Delete current pyodbc
2. easy_install pyodbc
3. import pyodbc

What is the expected output? What do you see instead?
I get the following error: 
ExtractionError: Can't extract file(s) to egg cache

The following error occurred while trying to extract file(s) to the Python egg
cache:

  [Error 5] Access is denied: 'C:\\Users\\jsalvatier\\AppData\\Roaming\\Python-Eggs\\pyodbc-2.1.7-py2.6-win32.egg-tmp\\pyodbc.pyd'

The Python egg cache directory is currently set to:

  C:\Users\jsalvatier\AppData\Roaming\Python-Eggs

Perhaps your account does not have write access to this directory?  You can
change the cache directory by setting the PYTHON_EGG_CACHE environment
variable to point to an accessible directory.

This bug is just a few hours old. If I swap back for a version of pyodbc that I 
deleted earlier today, it imports fine. 

I want to encourage pyodbc not to do stealth updates, but update the version 
number when the package is changed. That way these kinds of problems are easy 
to work around.

What version of the product are you using? On what operating system?
Windows 7

Please provide any additional information below.
 Python 2.6 32bit

Original issue reported on code.google.com by jsalvat...@gmail.com on 20 Aug 2010 at 9:17

[GoogleCodeExporter]

I'm not sure what a "stealth change" is.  What was the previous version you 
installed?

I believe I added a patch for egg support in 2.1.7, so it is possible that the 
previous version you had did not use eggs at all.  Perhaps the new egg patch 
needs more work.

Are you sure this isn't a bug in setuptools/easy_install?

Original comment by mkleehammer on 23 Aug 2010 at 4:16

• Changed state: Investigating

[GoogleCodeExporter]

Both version numbers are the same.

5ish days ago, I easy_installed pyodbc, and it worked fine. Then, last friday 
while trying to figure out an installer script, I deleted pyodbc and tried 
easy_installing it again. After I installed, it would not import, giving the 
the error given above. I was able to fix the problem by uninstalling the more 
recent egg and reinstalling the egg version that was in my recycle bin. If 
there has been no "stealth change" (change in the distribution without change 
in the version number), then I have no idea what could be causing this. 

Original comment by jsalvat...@gmail.com on 23 Aug 2010 at 4:25

[GoogleCodeExporter]

I see.  There were no stealth changes, so they should be exactly the same.

I'll leave this open for a bit and play with setuptools some more.  As you can 
guess I usually don't have to download pyodbc that way ;)

Original comment by mkleehammer on 24 Aug 2010 at 3:56

[GoogleCodeExporter]

I get the same issue in 3.0.6

Original comment by cyborg10...@gmail.com on 1 Apr 2013 at 9:38