Monday, January 15, 2007

Python on Windows and the PATH

Took me a few hours to track down a problem with importing win32com and getting "ImportError: DLL load failed: The specified module could not be found" which wasn't very clear. I doesn't even say what DLL it can't find!

Long story short, it boils down to python not being able to find the pywintypes25.dll, which is located in C:\Python24, but which is not in the PATH. Seems like having C:\Python25 added to PATH or some other solution would be a good idea. The problem wasn't even with the pywin32 package, which is what I expected and where I kept looking, but in the configuration and runtime environment of the python interpreter.

7 comments:

Anonymous said...

FileMonitor helps you
http://www.microsoft.com/technet/sysinternals/utilities/filemon.mspx

Anonymous said...

+1, had a similar problem and this helped me find the missing dll that was being searched for.
Cheers!

Ganesh Shamnur said...

It is not about the path alone:
If the current DLL being loaded refers to an additional DLL, the referred DLL needs to be present in the PYTHONPATH.
e.g:
a.dll is being loaded in python.
a.dll was created refering to b.dll.
So, make sure that both a.dll and b.dll are in the PYTHONPATH for proper loading.

Anonymous said...

Thank you for all your comments!

Had a similar problem, a dll (in PYTHONPATH) was loading an additional dll - it did not show it's name. I used Process Monitor (the new FileMonitor) to find out what that missing file was.

Ramprasad N said...

When I get the error "ImportError: DLL load failed: The specified module could not be found." in python, how can I know which dll it is searching for?
I dont know whether the reply will automatically reach my mail inbox. so please also mail me the reply to ramprasad85 at gmail.com

Thanks you

Anonymous said...

I'm not sure how old these comments are, but I'll add a comment since this is the first response in google for "python dll load failed."

I was able to fix this by importing pywintypes before win32api in the file that was producing the error. Give this a try, it fixed the problem for me...I guess we'll see if it causes a problem somewhere else...

Christopher said...

the pywintypes worked for me as well. Python3.2 here.

I write here about programming, how to program better, things I think are neat and are related to programming. I might write other things at my personal website.

I am happily employed by the excellent Caktus Group, located in beautiful and friendly Carrboro, NC, where I work with Python, Django, and Javascript.

Blog Archive