I've created custom report to track some params of new visitors from Google organic search. When I choose "landing page", the report returns pages like /orders/ or /order?id=xxxxx etc. The reality is that those pages can not become landings from search, because they are not represented there (closed from indexation). Also I've checked some queries, which drive visitors to those pages from search (if to believe UA), and the pages in SERP are different. What may cause such a data in UA's reports? I have some ideas, but need more to compare. Thank you in advance!
To answer you the main question - a "New User" in GA is a user without existing ga cookie for your website (meaning a regular visitor using private browsing for example, is counted as new user). The cookie is stored for 2 years, but using different browsers, different devices, private browsing and clearing the cookies delete the cookie, thus making the visitor "new user".
For your specific situation - there are many possible answers. Several example options to see non-indexed pages as landing pages:
- Direct visits (for example a user bookmarked the page, at later point
he cleared his cookies and visited the bookmarked page - making the
page landing, with new user);
- Referral Visits - somewhere someone posted/sent a link (email,
messenger, social media or some website), another visited the link - and you got landing page from new user;
- Another option is to get a visit through an image search - the page
may be deindexed, but that doesn't mean the images on that page
aren't in the SERP.
- If you have a search snippet in the SERP - you may get a visit from there too.
You will be able to check the exact source if you dig deeper in your reports.
About the different SERP - is nothing unusual, google serves completely different SERPS according to locations, devices, etc...