# CORS Problems out of the Blue **URL:** \ **Category:** Product Support\ **Created:** [June 29, 2022, 1:58pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614 "2022-06-29T13:58:26Z")\ **Posts on this page:** 7\ **Page:** 2
**Author:** ![mikew](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/mikew/32/5156_2.png) [@mikew](https://forum.mautic.org/u/mikew)\ **Post date:** [June 30, 2022, 11:29am UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/21 "2022-06-30T11:29:58Z")
I have now taken the tracking code and put it on a different site that I know is tracking and I still get this error: ```auto Failed to load resource: the server responded with a status of 500 () mtcevent ``` @joeyk ? ---
**Author:** ![joeyk](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/joeyk/32/11164_2.png) [@joeyk](https://forum.mautic.org/u/joeyk)\ **Post date:** [June 30, 2022, 12:52pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/22 "2022-06-30T12:52:43Z")
What is the event? Vanilla tracking code? ---
**Author:** ![joeyk](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/joeyk/32/11164_2.png) [@joeyk](https://forum.mautic.org/u/joeyk)\ **Post date:** [June 30, 2022, 12:54pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/23 "2022-06-30T12:54:06Z")
Does this point you any closer to your goal? [A new default Referrer-Policy for Chrome - strict-origin-when-cross-origin - Chrome Developers](https://developer.chrome.com/blog/referrer-policy-new-chrome-default/#:~:text=%23%20What%20does%20this%20change%20mean,the%20path%20and%20query%20string). ---
**Author:** ![techbill](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/techbill/32/8325_2.png) [@techbill](https://forum.mautic.org/u/techbill)\ **Post date:** [June 30, 2022, 1:39pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/24 "2022-06-30T13:39:13Z")
If you are getting error 500, I would check the ngnix error log. It may tell you something in there. That error log would be part of the ngnix log on the server which is not part of Mautic. You would probably would need to ask your server administrator to give you the copy of the error log if you don’t have root access. ---
**Author:** ![mikew](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/mikew/32/5156_2.png) [@mikew](https://forum.mautic.org/u/mikew)\ **Post date:** [June 30, 2022, 1:53pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/25 "2022-06-30T13:53:57Z")
Firstly thank you for everyone that tried to she some light on the matter and help out here. We found the problem and I have to say it was my fault. A long time ago we installed the MakeWebBetter plugin and this plugin on Wordpress went and created a ton of new custom fields which inevitably caused issues with creating new fields. When I wanted to add new fields I would have to go and delete one of the custom fields and my issue was I went and did this inside the database by dropping a column using the command ```auto alter tables leads drop column mob_whatever ``` This in turn started causing the error, and I must have done this about two weeks ago, and what happened was when Mautic went and wanted to create a new lead it would not find the correct column and was throwing a CRITICAL error that I simply ignored: ```auto Column not found: 1054 Unknown column 'mwb_newsletter_subs' in 'field lis ``` SO what I did was go into custom fields and delete these fields, and everything was working again. No idea what the CORS error was and why it was throwing that, but this is what fixed up the problem. It was a very uncomfortable day but I learnt a good lesson - Keep Calm and Read The Logs! Try and understand and isolate the issue. ---
**Author:** ![techbill](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/techbill/32/8325_2.png) [@techbill](https://forum.mautic.org/u/techbill)\ **Post date:** [June 30, 2022, 1:56pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/26 "2022-06-30T13:56:39Z")
Glad you got it all sorted and thanks for sharing the solution! ---
**Author:** ![silavapi](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.mautic.org/silavapi/32/7424_2.png) [@silavapi](https://forum.mautic.org/u/silavapi)\ **Post date:** [June 30, 2022, 1:57pm UTC](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614/27 "2022-06-30T13:57:30Z")
> [@mikew](#): > > Keep Calm and Read The Logs! I think we need to make this into a tshirt for the swag shop! Glad you got it sorted! [Previous page](https://forum.mautic.org/t/cors-problems-out-of-the-blue/24614.md?page=1)