Is it forbidden in Islam for a computer man or T.V. repair man or a doctor to enter the bedroom?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

If you mean that the marriageable man enters the bedroom while there are no women whom he is not permitted to look at, then there is no harm. However, if you mean that he will enter while there are women in the bedroom, then it is not permissible for him to enter except in case the women are covered with Hijab.

As regards a doctor entering to treat a woman, then this matter is detailed in Fatwa 82093, so please refer to it. 

Allaah Knows best.