Germany's Commerzbank said on Friday that net profit rose a better-than-expected 20% in the second quarter, helped by higher interest rates but dragged down by previously flagged problems at a Polish unit.

The bank raised its outlook for full year net interest income, now expecting 7.8 billion euros, up from previous expectations of around 7 billion euros. It cut its outlook for net commission income.

Commerzbank, one of Germany's best known banks and partially held by the government after a bailout more than a decade ago, is in the middle of a major overhaul, slashing its workforce and branch network to restore profits.

Like many banks, it is benefiting from a rise in interest rates and the income that generates, which was up 44% in the quarter from a year earlier.

Net profit of 565 million euros ($618.56 million) in the quarter compares with a profit of 470 million euros a year earlier. Analysts had on average expected profit of 538 million euros, according to a consensus forecast published by Commerzbank. ($1 = 0.9134 euros) (Reporting by Tom Sims and Frank Siebelt Editing by Miranda Murray and Friederike Heine)