Sometimes pushing to an HTTP repo fails with a useless message. abort: 'https://.../.../' does not appear to be an hg repository! Ought to produce a better diagnostics on the client. With patched 1.3.1, observed to produce an Apache HTML error message (from cgitb) including the vital text: File ".../hgwebdir.cgi", line 70, in ? wsgicgi.launch(application) File "mercurial/hgweb/wsgicgi.py", line 68, in launch File "mercurial/hgweb/hgwebdir_mod.py", line 91, in __call__ File "mercurial/hgweb/hgwebdir_mod.py", line 148, in run_wsgi File "mercurial/hgweb/hgweb_mod.py", line 100, in run_wsgi File "mercurial/hgweb/protocol.py", line 156, in unbundle File "mercurial/localrepo.py", line 2031, in addchangegroup File "mercurial/revlog.py", line 1204, in addgroup LookupError: 00manifest.i@......: unknown parent Might also be helpful if server's hgweb_mod.run_wsgi caught unexpected errors and returned a well-formed error response including the stack trace. The client patch would still be useful in this case, because it would let you diagnose issues with HTTP proxy servers and so on.