ver.2 PyGreSQL ERROR: from _pg import * ImportError: DLL load failed: The specified module could not be found

Question

I have the same problem that was discussed here, but I haven\'t credit to comment an answer so I start new question.

I have in PATH way to libpq.dll (C:\\PostgreSql

Answer 1

I was also facing the same issue on Win 8. First time I had installed PostgreSQL in "C:\Program Files" and also set environment PATH to point to PostgreSQL folder. I was suspecting permission issue for "C:\Program Files" folder.

I was able to fix this issue by following the steps as mentioned below.

• Uninstalled PostgreSQL
• Re-installed PostgreSQL in "C:\PostgreSQL" Note that I have not installed PostgreSQL into "C:\Program Files" folder this time
• Set the environment PATH C:\PostgreSQL\9.4;C:\PostgreSQL\9.4\bin
• Also ensure that _pg.pyd exist in C:\Python27\Lib\site-packages

Answer 2

I faced just the same issue; just to try my chance before doing what you say, I changed the PATH environment variable: I directly specified the whole directory path of libpq.dll OF THE ODBC DRIVER OF PostgreSQL (there are other "libpqdll"s as well in other relevant directories) which takes place in my Windows10 here: C:\Program Files\PostgreSQL\psqlODBC\bin .. and the problem is solved.. before, my PATH specification was C:\Program Files\PostgreSQL and I think the driver looked for the dll files directly here and either 1) when couldnt find directly in this specific diretory (by disregarding the subdirectories), 2) or came cross other "libpq.dll"s which didnt work for the driver, it gave the error message.. so here I come to the conclusion that it looks for the dll file OF THE ODBC DRIVER in PATH env.varible, so I needed to specify in the PATH environment variable directly the directory of the PostgreSQL's ODBC driver I used, psqlODBC .. for future needs I wanted to write those details:)

Answer 3

I got the same error on Win10 with Python 3.5 and Python 3.8, both are 64bit, and Postresql 12, also 64bit. DLL locations "c:\Program Files\PostgreSQL\12\bin" and "c:\Program Files\PostgreSQL\psqlODBC\bin" were added to the PATH but it caused another error:

• "from _pg import * ImportError: DLL load failed: The operating system cannot run %1."

Then I've checked what is going on with Process Monitor from Sysinternals and found that libpg.dll was looking for other DLLs. Finally, the following files:

• libpq.dll
• libssl-1_1-x64.dll
• libcrypto-1_1-x64.dll

were copied from "c:\Program Files\PostgreSQL\12\bin" folder to:

• "c:\Users...\AppData\Local\Programs\Python\Python35"
• "c:\Users...\AppData\Local\Programs\Python\Python38"

folders and now "import pg" works fine in both versions of Python.