Please refactor calendar language file at modules\Calendar (lines 164 to 2016)
https://github.com/salesagility/SuiteCRM/blob/master/modules/Calendar/language/en_us.lang.php
The actual arrays needs to be changed a key-value style instead of the actual hardcoded language.
Else those lines should go into a separated file so it doesn't have to have the same array style as the SuiteCRM language files.
Actual arrays example:
$mod_list_strings = array(
'dom_cal_weekdays'=>
array(
"Sun",
"Mon",
"Tue",
"Wed",
"Thu",
"Fri",
"Sat",
),
'dom_cal_weekdays_long'=>
array(
"Sunday",
"Monday",
"Tuesday",
"Wednesday",
"Thursday",
"Friday",
"Saturday",
),
'dom_cal_month'=>
array(
"",
"Jan",
"Feb",
"Mar",
"Apr",
"May",
"Jun",
"Jul",
"Aug",
"Sep",
"Oct",
"Nov",
"Dec",
),
'dom_cal_month_long'=>
array(
"",
"January",
"February",
"March",
"April",
"May",
"June",
"July",
"August",
"September",
"October",
"November",
"December",
),
Update: even with those lines translated the calendar body is not translated. Same goes for time format that keep display in 11:pm and not 23:00
Suite CRM 7.7.8 (SuiteP and Suite R) + General settings and user settings all reset to same format.



@likhobory is your calendar columns translated (day and format hour)?
I have the same problem.
@shogunpol re-confirmed as a bug for SuiteCRM 7.7.8
I confirm. There is the problem with resource Calendar as well - days of week and months cannot be translated
@maladrill @likhobory can you test this PR: Calendar Localization not working: days long and time slot by Szellszi https://github.com/salesagility/SuiteCRM/pull/2983
It works.

@Dillon-Brown Calendar translation for days, months (and long hour format) are now OK (7.9.0 RC version- applied 2 PR fix: #2983 and yours #3565 + quick repair + JS language repair)
On the Resources calendar (see above pic from maladrill) it is not translated yet.
Maybe its better for me to open a new Issue?
@horus68 These are technically 3 separate issues, key-value, calendar localisation and resources calendar. So feel free to create another one for just the resources calendar.