I’ve been using Sketchup 2016 lately and when I import objects in trimble, it usually works fine. Somehow today, nothing seems to ben working. Every time I try to download an object (even the older versions), a pop up notifies me that i need a newer version. How can I fix this problem???
Generally speaking, older versions cannot open content created in newer versions. So you would need to upgrade to get those models or request the person who made the model to “save in a legacy format” i.e. and older version. In the SU “save as” dropdown it can be saved as an older version.
Christine Eneroth has made a plugin that will allow the opening of newer models on older versions but I don’t think you can have an extension in the free web version.
Your username suggests that you might be a designer by profession. If so, you are using a version of Sketchup not intended for commercial use. You need Pro anyway if you are using it for work.