Hello,
As a result of updating my schedule on some activities it automatically inserted a start no earlier than constraint, for example when i told the project to schedule unstarted activties after current data date.

Is having these constraints bad for my schedule logic? especially after i do other updates later on that version?

Also is there a way to remove all these alltogether at once or we can only remove these constraints one by one. (to make it start as soon as possible)

by making them start as soon as possible actually is more healthy as far as the schdule loogic as long as i do the correct schedule logic instead of not correcting the wrong logic and inserting actual dates am i right?

As a result of updating my schedule on some activities it automatically inserted a start no earlier than constraint, for example when i told the project to schedule unstarted activties after current data date.

This is expected as part of the reschedule. If the tasks retained the ASAP constraint, they would be scheduled in the past.

Is having these constraints bad for my schedule logic? especially after i do other updates later on that version?

No. If the tasks have constraints from the reschedule command that is, in my opinion, better than remaining work in the past. If you run another update and the task still has remaining work, that will be rescheduled again to the future.

Also is there a way to remove all these alltogether at once or we can only remove these constraints one by one. (to make it start as soon as possible) by making them start as soon as possible actually is more healthy as far as the schdule loogic as long as i do the correct schedule logic instead of not correcting the wrong logic and inserting actual dates am i right?

Select all tasks, show the task information dialog box. Go to the Advanced tab and change the constraint. However, that will force remaining work in the past.

Again - there is a difference between constraints forced by progressing the project and using constraints (usually through typing dates) in the initial planning. You should have both correct scheduling logic driven by task predecessor and successor relationships initially. Actuals (actual start, actual finish, actual work, etc) over-ride that scheduling logic and constraints added by rescheduling is more logical than incomplete tasks in the past.