Aspire E15 will not operate on battery power if the memory or hard drive access doors are not installed correctly - Acer Community
8GB Memory PC3 RAM for Acer Aspire E, E1, E3, E15, ES1, ES14, F, One 14 Series | eBay
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Acer Aspire E15 Touchscreen Laptop, Model E5-571P-59QA, Intel Core i5-421OU Processor, 15.6" HD Multi-touch LCD, Intel HD Graphics 4400, 4Gb RAM, 500Gb HDD, DVD Super Multi DL Drive, Windows 8.1 64 bit