Aliso Viejo-based Smith Micro Software Inc. on Wednesday reported second quarter earnings that missed Wall Street expectations and announced plans to close offices and lay off workers amid lackluster sales. Investors seized on the news and sent shares down about 10% in midday trading Thursday to a market value of $38.75 million. The company reported revenue of $10.5 million in the recently ended quarter, up 3.1% from a year earlier. Analysts on average had forecast sales of about $12.4 million. It posted an adjusted loss, which excludes stock compensation and non-cash tax expenses, of $3.8 million, compared to an adjusted loss of $3.6 million a year earlier. Wall Street had expected a loss of about $2.6 million. Smith Micro makes software for cell phones and connecting mobile devices to wireless networks.