ERROR_WINHTTP_NAME_NOT_RESOLVED when using dbghelp as a service

I am trying to setup a symbol proxy server that targets both our own internal symbol stores (UNC) and http servers (microsofts being one). I want it to run as a service, or as IIS (which runs as a service of course).

I have tried Micrsoft SymProxy, and am now trying pySymProxy. pySymProxy works just fine when I run it from desktop, but has this WINHTTP error when run as a service (/via IIS).

I have tried every fix mentioned here, including using the DBGHELP_WININET, and setting the registry settings. These have no effect at all. I believe this information is out of date now, but I can't find anywhere that suggests what the latest recommendation for this is. I also don't understand what the underlying problem is either. Every method I have tried so far tells me I am NOT behind a proxy. WinHttp says it is not using a proxy in the log entry, so why can it not simply resolve a name like it can when run from the desktop?

Example from my log when it fails, while running from a service:

SYMSRV:  BYINDEX: 0x4           C:\SymProxy\cache*http://msdl.microsoft.com/download/symbols           kernelbase.pdb           0C3B0BCF250566567FA913502B5677C81  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\kernelbase.pdb - path not found  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\kernelbase.pd_ - path not found  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\file.ptr - path not found  SYMSRV:  WinHttp interface using proxy server: none  SYMSRV:  HTTPGET: /download/symbols/index2.txt  SYMSRV:  WinHttpSendRequest: 800C2EE7 - ERROR_WINHTTP_NAME_NOT_RESOLVED  SYMSRV:  HTTPGET: /download/symbols/kernelbase.pdb/0C3B0BCF250566567FA913502B5677C81/kernelbase.pdb  SYMSRV:  WinHttpSendRequest: 800C2EE7 - ERROR_WINHTTP_NAME_NOT_RESOLVED  SYMSRV:  RESULT: 0x800C2EE7  

Example of it working totally fine when run from desktop:

SYMSRV:  BYINDEX: 0x4           C:\SymProxy\cache*http://msdl.microsoft.com/download/symbols           kernelbase.pdb           0C3B0BCF250566567FA913502B5677C81  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\kernelbase.pdb - path not found  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\kernelbase.pd_ - path not found  SYMSRV:  UNC: C:\SymProxy\cache\kernelbase.pdb\0C3B0BCF250566567FA913502B5677C81\file.ptr - path not found  SYMSRV:  HTTPGET: /download/symbols/index2.txt  SYMSRV:  HttpQueryInfo(HTTP_QUERY_CONTENT_LENGTH): 800C2F76 - ERROR_HTTP_HEADER_NOT_FOUND  SYMSRV:  HttpQueryInfo: 80190194 - HTTP_STATUS_NOT_FOUND  SYMSRV:  HTTPGET: /download/symbols/kernelbase.pdb/0C3B0BCF250566567FA913502B5677C81/kernelbase.pdb  SYMSRV:  HttpQueryInfo: 801900c8 - HTTP_STATUS_OK  SYMSRV:  kernelbase.pdb from http://msdl.microsoft.com/download/symbols: 7687168 bytes -  

https://stackoverflow.com/questions/66752310/error-winhttp-name-not-resolved-when-using-dbghelp-as-a-service March 23, 2021 at 03:03AM