After suffering an excruciating computer glitch that caused pricing problems, Bank of New York Mellon Corp's calculating system seem to be back to normal now. 

BNY Mellon may be finally starting to get its net asset values calculation back to normal after a high-profile technology glitch In a SunGard accounting system, which caused chaos last week. The bank said it will come up with strategies to make sure the same type of failure will not happen again.

BNY Mellon chief executive expects to fix the pricing problems in the U.S. mutual funds and exchange-traded funds before the markets open on Monday. 

The issues with the pricing were caused by a computer glitch. It affected the calculations of assets amounting to billions of dollars last week. This problem has taken longer than what was expected, according to CEO Gerald Hassell.  

Hassell said they aim to give fund clients with system-generated NAV for Monday as soon as tomorrow night. "We expect to complete Friday's NAVs for all but one of the affected fund clients by tomorrow morning."

The pricing glitch had investors frustrated with almost 50 fund companies not being able to give an accurate value for their holdings.

There were more than 100 employees at the BNY Mellon worked even during the weekends to make sure the glitch will be corrected to provide accurate and up-to-date pricing for some 1,200 mutual funds and exchange-traded funds that are having problems with the right values since last Monday.

On Sunday, BNY Mellon was able to calculate the net asset values of all the funds through last Wednesday; however, it wasn't able to finish one company, which BNY didn't name.

The bank was still working on a backlog from Thursday to Friday. Some of the companies the glitch affected were Goldman Sachs Group Inc, Prudential Investments, Guggenheim Investments, Invesco PowerShares, and Federal Investors.

All the affected companies relied on back up methods to calculate the asset values. Now, they are correcting the data they published last week with new, accurate ones.

According to data from Morningstar and Lipper, when the calculation system of BNY Mellon broke down last weekend, it disrupted pricing on 5 percent of U.S. mutual funds and ETFS with assets that amounts to $404 billion.

Hassell said they still don't know the cause of the glitch and that they would get aide from independent third party to work on the problem.