You Can easy fix the  QuickBooks running slow error by performing
Upgrade workstations to speed up QuickBooks.Upgrade to a solid-state drive.Ensure that you are using a 64-bit computer and an additional fast clock speed of 2.2GHz or more. Upgrade the Ram of your computer to 8GB or higher.Invest in a faster network connection with rotational speed above 7,500 rpm.
https://blogulr.com/QBrunningslow
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