E39 Key or Alarm problems?

[Truvalu]

About a year ago, the E39's keys were "misplaced".
Wife had the car opened and received another key. (apparently it took many, many hours to get into this car)

Since then she had non-stop problems with the key. Either the housing is bad, or the key does not unlock or something.

I would like to know if one can upgrade this key to a newer type key? (Monday)

(Today)
The wife's been told now that the problem is with the "aftermarket" alarm system that was fitted.
I thought this car came with alarm fitted??

Baffled!
Now to have her take it to alarm dudes, Drive-sure, who opened the car as above or is it a question of diagnostic, computer settings?

Any suggestions, please?

 

[spawn616]

the new key needs to be coded

its not hard you just hold down the buttons on the remote in a sequence (google will have it) and voila