NEW DELHI  When 7-year-old Shiva Ayyadurai left Mumbai with his family nearly 40 years ago, he promised himself he would return to India someday to help his country.

In June, Mr. Ayyadurai, now 45, moved from Boston to New Delhi hoping to make good on that promise. An entrepreneur and lecturer at the Massachusetts Institute of Technology, with a fistful of American degrees, he was the first recruit of an ambitious government program to lure talented scientists of the so-called desi diaspora back to their homeland.

“It seemed perfect,” he said recently of the job opportunity.

It wasn’t.

As Mr. Ayyadurai sees it now, his Western business education met India’s notoriously inefficient, opaque government, and things went downhill from there. Within weeks, he and his boss were at loggerheads. Last month, his job offer was withdrawn. Mr. Ayyadurai has moved back to Boston.

In recent years, Mother India has welcomed back tens of thousands of former emigrants and their offspring. When he visited the United States this week, Prime Minister Manmohan Singh personally extended an invitation “to all Indian-Americans and nonresident Indians who wish to return home.” But, like Mr. Ayyadurai, many Indians who spent most of their lives in North America and Europe are finding they can’t go home again.