Hello, I can upload a file to my Apache web server using Curl just fine: echo "[$(date)] file contents." | curl -T - http://WEB-SERVER/upload/sample.put However, if I put a Squid proxy server in between, then I am not able to: echo "[$(date)] file contents." | curl -x http://SQUID-PROXY:3128 -T - http://WEB-SERVER/upload/sample.put Curl reports the following error: *Note: The following error response was in HTML format, but I've removed the tags for ease of reading.* ERROR: The requested URL could not be retrieved ERROR The requested URL could not be retrieved While trying to retrieve the URL: http://WEB-SERVER/upload/sample.put The following error was encountered: Unsupported Request Method and Protocol Squid does not support all request methods for all access protocols. For example, you can not POST a Gopher request. Your cache administrator is root. My `squid.conf` doesn't seem to be having any ACL/rule that should disallow based on the `src` or `dst` IP addresses, or the `protocol`, or the HTTP `method`... **as I can do an `HTTP POST` just fine between the same client and the web server, with the same proxy sitting in between.** In case of the failing `HTTP PUT` case, to see the request and response traffic that was actually occurring, I placed a `netcat` process in between Curl and Squid, and this is what I saw: **Request:** PUT http://WEB-SERVER/upload/sample.put HTTP/1.1 User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5 Host: WEB-SERVER Pragma: no-cache Accept: */* Proxy-Connection: Keep-Alive Transfer-Encoding: chunked Expect: 100-continue **Response:** HTTP/1.0 501 Not Implemented Server: squid/2.6.STABLE21 Date: Sun, 13 May 2012 02:11:39 GMT Content-Type: text/html Content-Length: 1078 Expires: Sun, 13 May 2012 02:11:39 GMT X-Squid-Error: ERR_UNSUP_REQ 0 X-Cache: MISS from SQUID-PROXY-FQDN X-Cache-Lookup: NONE from SQUID-PROXY-FQDN:3128 Via: 1.0 SQUID-PROXY-FQDN:3128 (squid/2.6.STABLE21) Proxy-Connection: close <SNIPPED the HTML error response already shown earlier above> *Note: I have anonymized the IP addresses and server names throughout for readability reasons.* *Note: I had posted this question on [StackOverflow also][1], but got no helpful response. Posting it here, in case people on StackOverflow are seeing this as a non-programming question and not taking interest.* Regards, /HS [1]: http://stackoverflow.com/questions/10568655/unable-to-test-http-put-based-file-upload-via-squid-proxy