The importance of 3D printing as a builder of the digital future is growing all the time. When it comesto the digital future, one clear goal is that, for example, spare parts are no longer necessarily shippedfrom factories around the world, but are 3D printed using a digital model of the spare part purchasedfrom the manufacturer. Using 3D printers for replacement printing or home use is relatively simple.However, with 3D printers, you come across a wide variety of situations that require fault detection,troubleshooting, and general adjustment. This article highlights the most common problems with 3Dprinters. The technologies chosen for this study are Vat Photopolymerization and FDM (FusedDeposition Modeling) printing technologies because they are very common techniques for spare partsprinting and home use. This study was conducted in concrete way, experimenting and producingproblems intentionally, then solving them with solutions and techniques, which are common and gainedthrough experience. As a result, this article is written as a guide to the most common problems withthese chosen technologies. Solutions to the problems are showcased in simple and effective steps. Afterall, this study showed well the diversity of problem situations in 3D printing as well as the need forconcrete expertise in troubleshooting solutions. The problems faced and tackled in this study were themost common ones but there can exist other problems too.