Hello everyone as the topic title I am wondering how to delete the sim contact with the N900 ?? Or is there any way that I could connect through wifi to my pc and delete it from my PC ? hope to get some reply from maemo community since I already run out of idea and the N900 is the only phone I have

No can do unfortunately. You can only read SIM contacts to the phone, you can't manipulate things in the other direction.

Sadly the only option you have (at the moment) is to stick your SIM in a regular phone and do it there.

But we could transfer and backup our contacts with WinSCP is that possible ? Hmm that quite annoying where you should bring out your battery and get another phone and delete contact right there sigh hope in the future there will have a solution for this issues

You could backup the database file absolutely - strictly speaking this is what the 'backup' application does already, but if you want to do it manually with winscp simply copy:

/home/user/.osso-abook/addressbook.db

This is a berkeley database so you can't do a whole lot with it unless you have the tools available to manipulate it.

Okay hope there will be some update regarding the delete sim card contacts with the N900 or HOPE there would be a PR1.3 updates !