Investors encounter trading issues at some brokerages

Investors ran into trading difficulties Monday as several leading brokerage firms experienced technical issues that limited user access. Charles Schwab said it had technical issues earlier, which led to some clients being unable to access their accounts. TD Ameritrade and Vanguard also reported difficulties. The problems arose amid a market surge.  The S&P 500 jumped Monday and is is on track to close at a record for the first time in more than two months, helped by encouraging early da