Vanguard's website, vanguard.com, intermittently gave users a "this webpage is not available" error after login information is entered into the site.
Users were quick to sound off about it on Twitter.
can't logon to vanguard THE WORLD IS ENDING
— biracial af (@alyssakeiko) August 24, 2015
Observation: @Vanguard_Group site appears to be struggling mightily.
— Ben Casselman (@bencasselman) August 24, 2015
@Vanguard_Group so who should send the bill to for the opportunity cost of being unable to trade in my brokerage account today? @cnbc
— Ed (@emcilveen) August 24, 2015
@Vanguard_Group Your brokerage system is not working.
— Ilya Talman (@RoyTalman) August 24, 2015
Vanguard hosts investment portfolios for customers, which includes mutual funds, 401(k) and IRAs.
Linda Wolohan, a spokeswoman for Vanguard, said there was a surge of traffic Monday morning.
"We experienced a brief period of sporadic website inaccessibility at the start of the trading day. We've added capacity to manage the volume," Wolohan said. "During this brief period, clients had the option to call to conduct transactions or check balances. Or they're calling merely for reassurance."
RELATED: Stocks plummet on Wall Street as global sell-off continues
Are you having trouble logging in to your investment account? Let us know in the comment section below.