How should I deal with "'someFunction' is not an exported object from 'namespace:somePackage'" error?

Some reasons:

• Function is not part of the package, anymore, try ??someFunction to find out which package it belongs to.
• Package data is not part of the package
• Function is available in newer version of the package, reinstall latest version.

See also these questions referring to specific instances of this problem:

• Error: 'use_package' is not an exported object from 'namespace:devtools'
• 'data' is not an exported object from 'namespace:my_package'
• Error: 'st_normalize' is not an exported object from 'namespace:sf' when using 'geom_sf()'
• R Error: 'overlay' is not an exported object from 'namespace:sp'
• 'stopwords' is not an exported object from 'namespace:tokenizers'
• Error: 'is_latex_output' is not an exported object from 'namespace:knitr' in Rmarkdown
• R package Error: 'encode_colour' is not an exported object from 'namespace:farver'
• R Markdown Error: 'is_latex_output' is not an exported object from 'namespace:knitr'
• Error: 'StatIdentity' is not an exported object from 'namespace:ggplot2' when calling ggmap in R
• Data not exported from namespace in R