There was an error processing your request, please try again at a later time.

So I had installed a new module for quickbooks which i needed and had to roll back the system from php 7.2 to php 7.1 as well as install curl and another module called ionCube. however once the install was completed and i did a full repair all pages had a error on it basically. I was able to remove the error by going to AJAX and disabling all the modules in ajax and then doing a full repair. However I’m wondering if having all the ajax is good or bad? but any time i try for instance to re-enable the accounts module ajax it just does the same error “There was an error processing your request, please try again at a later time.” and the in the console i get this:

Failed to load resource: the server responded with a status of 500 (Internal Server Error)
Uncaught AjaxUI error parsing response
Failed to load resource: the server responded with a status of 404 (Not Found)
Uncaught AjaxUI error parsing response

Any thoughts? Thank you in advance!

Sometimes Ajax fails because error_reporting is set in such way that warnings and other useless messages are returned. When that happens, the ajax call may be fed with wrong data and may cause a failure because it will try to use the received data thinking that it has a specific format.