INTL_IDNA_VARIANT_UTS46 - Can't login

[Gavlarr94]

When i install a fresh Prestashop i can't login to the backoffice. I get this error when i try to login as admin:

 (1/1) ContextErrorException

Warning: Use of undefined constant INTL_IDNA_VARIANT_UTS46 - assumed 'INTL_IDNA_VARIANT_UTS46' (this will throw an Error in a future version of PHP)

Which is the same error i get when i have debug mode on when i try login to the front office as a customer.

I can fix the back office error by adding intval(INTL_IDNA_VARIANT_UTS46));

But i get the same error when an old customer account tries to login to the front office.

Our server uses php 7.3 (the only option available).
Prestashop 1.7.7.0 says it is compatible with it now.

Any suggestions?

Thanks,
Gav

[PrestaHeroes USA]

Gav,

if you search for that error there are several reports, github, .cs forum...etc.

for me this looks like issue with hosting.  Some Hosters run new PHP versions with old intl/icu.

see if you can find answer via following search that fits your scenaio

https://www.google.com/search?ei=HPvwX-uzMse05NoP7cWagA8&q=prestashop+Warning%3A+Use+of+undefined+constant+INTL_IDNA_VARIANT_UTS46+-+assumed+'INTL_IDNA_VARIANT_UTS46'&oq=prestashop+Warning%3A+Use+of+undefined+constant+INTL_IDNA_VARIANT_UTS46+-+assumed+'INTL_IDNA_VARIANT_UTS46'&gs_lcp=CgZwc3ktYWIQAzoECAAQR1DcHliRNWDmOGgAcAJ4AIABpQGIAfgGkgEDMC42mAEBoAEBqgEHZ3dzLXdpesgBCMABAQ&sclient=psy-ab&ved=0ahUKEwjrsbKdrf7tAhVHGlkFHe2iBvAQ4dUDCA0&uact=5