Trading on the Spanish stock exchange was suspended for hours due to a technical fault.
Before being halted just after the markets opened on Monday, the Ibex was up 0.25% at 6,772 points.
The glitch comes days after the New York Stock Exchange was sent into chaos after leading brokerage firm Knight Capital (NYSE: KCG - news) experienced a technical error with its automated trading software.
The IT meltdown caused the firm to make dozens of erroneous trades, which resulted in a $440m (£283m) loss to the company.
Many have cautioned the use of high-speed trading software in stock exchanges and the latest technical glitch will fuel such questions over their reliability.
Reports say the Madrid stock exchange system has recently been upgraded, but is still not as sophisticated or fast as that of many European rivals.
The latest computer glitch will add to tension on trading floors, as investors continue to lack confidence in the midst of a financial crisis.
Following the restart mid-afternoon, trading quickly boosted the Ibex and it ended the day up 4.41%.
In Italy the Mib closed 1.5% higher.
More From Sky News