Wachovia Securities was dogged by computer glitches last week which prevented brokers from accessing accounts, placing trades and transferring funds, according to a report by the Wall Street Journal.
The problems started when brokers from Wachovia and the former Prudential Securities went live with a new single platform, which was developed by Thomson Financial.
In February this year, Thomson Financial won a five year contract worth $200 million with Wachovia Securities - which merged with Prudential Securities last year - to supply its Thomson One premium desktop product and Beta Systems trade processing software.
WSJ says about 5000 employees were blocked from logging onto computers last Tuesday, and the breakdowns escalated during the course of the week.
According to the report, Thomson Financial says the problems the brokers had with computer access didn't result from the desktop system it supplied.