Answers.Body: <p>This seems like it might be your CiviCRM not having a single canonical URL.</p>
  
  <p>CiviCRM form processing requires a canonical URL to be set. If your site is configured to use <code>http://example.org</code> and the visitor lands on <code>http://www.example.org</code>, CiviCRM's form processing will redirect them to the configured base URL part way through the contribution flow and fail (because the user's cookies no longer are supplied).</p>
  
  <p>I can't load the URL you've linked to, but if I start the Join process at the first URL below, I am able to get to PayPal. If I start at the second URL below, I see the "too many redirects" notice you describe.</p>
  
  <ul>
  <li><code>http://isebiogeochemistry.com/index.php/iseb-membership</code></li>
  <li><code>http://www.isebiogeochemistry.com/index.php/iseb-membership</code></li>
  </ul>
  
  <p>Finding your site via Google ("ise biogeo chemistry") leads me to the latter hostname.</p>
  
  <p>To prevent this (mis) behaviour, both the protocol (http vs https) and the hostname (example.org vs www.example.org) must be consistent (ideally, enforced with a redirect from ANY wrong URL to the single "correct" one).</p>
  
  <p>How to configure canonical URLs varies between webserver and CMS, so I won't document that here. You'll find plenty of good existing docs with a search for eg "(your CMS) + canonical URL plugin", or "(your webserver) canonical URL".</p>
  
  <p>Some similar questions on CiviCRM Stack Exchange:</p>
  
  <ul>
  <li><a href="https://civicrm.stackexchange.com/questions/3218/network-error-unable-to-reach-the-server/3233#3233">**Network Error - Unable to reach the server</a></li>
  <li><a href="https://civicrm.stackexchange.com/questions/6790/network-error-due-to-cross-origin-request-blocked/6824#6824">Network Error due to Cross-Origin Request Blocked</a></li>
  <li><a href="https://civicrm.stackexchange.com/questions/6271/payment-options-do-not-display-when-https-used-only-when-http-used/6280#6280">Payment options do not display when https used only when http used</a></li>
  <li><a href="https://civicrm.stackexchange.com/questions/2422/could-not-find-a-valid-session-key-unable-to-save-any-admin-forms/2900#2900">&quot;Could not find a valid session key.&quot; Unable to save any admin forms</a></li>
  </ul>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2017-03-07T19:29:52.760Z
Answers.LastActivityDate: 2017-03-07T20:16:06.183Z
Answers.LastEditDate: 2017-04-13T12:53:13.207Z
Answers.UserDisplayName: Chris Burgess
Body: <p>The CiviCRM (4.7.14) membership sign-up page for our website will not always connect to Paypal (standard), our payment processor.  Sometimes it works, mostly not.  In Firefox, the error message is: "The page isn’t redirecting properly Firefox has detected that the server is redirecting the request for this address in a way that will never complete. This problem can sometimes be caused by disabling or refusing to accept cookies."  I have checked settings in CiviCRM and with Paypal, and everything looks OK as far as I can tell. Looking for help to get this issue fixed.</p>
  
  <p>Our site is on Joomla 2.5.20 and appears to be up to date. To the best of my knowledge, the connect to Paypal worked fine until about 6 months ago. Since then, CiviCRM was updated to 4.7.14. The problem is not unique to Firefox; complaints also come from people using Edge, Chrome, Safari in different countries all around the world. Doesn't seem to be a difference for a logged-in user or non-logged-in visitor.  </p>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-03-07T17:20:09.920Z
Comments.Text: Welcome to StackExchange! This looks like a good question.  You could improve it by adding the version of the CMS you are using (e.g. Drupal, WordPress or Joomla).  This may make a difference to some answers.
Comments.UserDisplayName: William Mortada
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2017-03-07T17:58:00.713Z
Comments.Text: Has it ever worked, maybe on a previous version?  Can you tell what url it's trying to go to?  Does that url work in a new window by itself?  If it's a browser caching or cookie thing, it might work in a private session?
Comments.UserDisplayName: Paul-Tahoe
Tags: <civimember><payment-processor><paypal>
Title: Problem connecting to payment processor
ThreadText: # Problem connecting to payment processor
  
  (Asked by: username_0 on 2017-03-07)
  
  The CiviCRM (4.7.14) membership sign-up page for our website will not always connect to Paypal (standard), our payment processor. Sometimes it works, mostly not. In Firefox, the error message is: "The page isn’t redirecting properly Firefox has detected that the server is redirecting the request for this address in a way that will never complete. This problem can sometimes be caused by disabling or refusing to accept cookies." I have checked settings in CiviCRM and with Paypal, and everything looks OK as far as I can tell. Looking for help to get this issue fixed.
  
  Our site is on Joomla 2.5.20 and appears to be up to date. To the best of my knowledge, the connect to Paypal worked fine until about 6 months ago. Since then, CiviCRM was updated to 4.7.14. The problem is not unique to Firefox; complaints also come from people using Edge, Chrome, Safari in different countries all around the world. Doesn't seem to be a difference for a logged-in user or non-logged-in visitor.
  
  **Tags:** civimember, payment-processor, paypal
  
  > **Comments:**
  > **username_1**: Welcome to StackExchange! This looks like a good question.  You could improve it by adding the version of the CMS you are using (e.g. Drupal, WordPress or Joomla).  This may make a difference to some answers.  
  > **username_2**: Has it ever worked, maybe on a previous version?  Can you tell what url it's trying to go to?  Does that url work in a new window by itself?  If it's a browser caching or cookie thing, it might work in a private session?  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_3 on 2017-03-07. Score: 1 | Accepted answer
  
  This seems like it might be your CiviCRM not having a single canonical URL.
  
  CiviCRM form processing requires a canonical URL to be set. If your site is configured to use `http://example.org` and the visitor lands on `http://www.example.org`, CiviCRM's form processing will redirect them to the configured base URL part way through the contribution flow and fail (because the user's cookies no longer are supplied).
  
  I can't load the URL you've linked to, but if I start the Join process at the first URL below, I am able to get to PayPal. If I start at the second URL below, I see the "too many redirects" notice you describe.
  
  * `http://isebiogeochemistry.com/index.php/username_0-membership`
  * `http://www.isebiogeochemistry.com/index.php/username_0-membership`
  
  Finding your site via Google ("ise biogeo chemistry") leads me to the latter hostname.
  
  To prevent this (mis) behaviour, both the protocol (http vs https) and the hostname (example.org vs www.example.org) must be consistent (ideally, enforced with a redirect from ANY wrong URL to the single "correct" one).
  
  How to configure canonical URLs varies between webserver and CMS, so I won't document that here. You'll find plenty of good existing docs with a search for eg "(your CMS) + canonical URL plugin", or "(your webserver) canonical URL".
  
  Some similar questions on CiviCRM Stack Exchange:
  
  * [\*\*Network Error - Unable to reach the server](https://civicrm.stackexchange.com/questions/3218/network-error-unable-to-reach-the-server/3233#3233)
  * [Network Error due to Cross-Origin Request Blocked](https://civicrm.stackexchange.com/questions/6790/network-error-due-to-cross-origin-request-blocked/6824#6824)
  * [Payment options do not display when https used only when http used](https://civicrm.stackexchange.com/questions/6271/payment-options-do-not-display-when-https-used-only-when-http-used/6280#6280)
  * ["Could not find a valid session key." Unable to save any admin forms](https://civicrm.stackexchange.com/questions/2422/could-not-find-a-valid-session-key-unable-to-save-any-admin-forms/2900#2900)
  
  
  ---
  
  