Analytics Overwriting Other Cookies?

[ronalthan900z]

Has anyone ever noticed lower reported sales in other conversion tracking tools while using Google Analytics? In particular, I've noticed it across all other platforms, after implementing a new utm source/medium tag to track in Analytics.
Is it possible that Analytics cookies can overwrite other cookies?

If so, is this particular to Google Analytics, or would it be caused by any analytics package?

[keyplyr]

Hello ronalthan900z and welcome to WebmasterWorld [webmasterworld.com]

[ronalthan900z]

:)
tks admin
Nice to meet admin

[lucy24]

The word “overwrite” is a bit of a misnomer. There’s really just one vast cumulative cookie string. (Analogy to Roach Motel presents itself.)

That being said:

Is it possible that Analytics cookies can overwrite other cookies?

No. Only your server can give instructions about cookies. Unless, that is, you’ve goofed in a phenomenal way by giving your own cookies exactly the same name as GA cookies (typically beginning in utm_blahblah). Or some cookie-setting third party has made this error, which does not seem wildly likely.

[RhinoFish]

"Has anyone ever noticed lower reported sales in other conversion tracking tools while using Google Analytics? In particular, I've noticed it across all other platforms, after implementing a new utm source/medium tag to track in Analytics."

Can you clarify exactly what you mean here? Like you had tracking system XYZ, like an affiliate network for example, then you added Analytics and started tagging some links with utm tags, and now tracking system XYZ reports fewer sales than before? Are you tagging the traffic that comes from XYZ, or some other bucket of traffic?

[Steven29]

"No. Only your server can give instructions about cookies."

What about JavaScript cookies?

[lucy24]

What about JavaScript cookies?

What about them? Scripts originate in your server. That is: the script itself may live elsewhere, in the same way that fonts or ads may be pulled in from some other location, but ultimately it has to be referenced in your own page or the visitor's browser wouldn't know about it.

Now, if a human has saved a page locally, scripts and all, then they may end up executing scripts--including ones that set cookies--that are no longer invoked by your live site. But this doesn't affect you.