When Blazemeter performance tests run into errors (as listed in the errors tab), it often proves to be useful to examine the error.jtl file.
This file is included in artifacts.zip, downloadable from the logs tab. The file holds full details of all failed samplers but is hard to read by any editor.
To improve readability, it is recommended to load the file into Jmeter's View Result Tree Listener
However doing so, it may become apparent that the number of entries in this listener is far less than the number of errors reported in the Blazemeter errors tab.
Because of this, a particular error that you are trying to resolve may not be included in the View Result Tree Listener, making it impossible to determine the root cause of that specific error.