How should I deal with "package 'xxx' is not available (for R version x.y.z)" warning?

How should I deal with "package 'xxx' is not available (for R version x.y.z)" warning?

r installation repository package r-faq

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How to unload a package without restarting R

r package r-faq

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What is the difference between require() and library()?

r package r-faq

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How to find out which package version is loaded in R?

r package version

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How do I install an R package from source?

r package installation r-faq

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How to select a CRAN mirror in R

r package installation cran

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Problems installing the devtools package

r package devtools

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How to organize large R programs?

r package conventions code-organization project-organization

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R install.packages returns "failed to create lock directory"

r package rcpp

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Function to calculate geospatial distance between two points (lat,long) using R [duplicate]

r package geospatial distance latitude-longitude

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Cannot install R-forge package using install.packages

r svn installation package r-forge

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Diagnosing R package build warning: "LaTeX errors when creating PDF version"

r error-handling package

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Warning about UTF-8 with roxygen2

r utf-8 package roxygen2

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Create an R package that depends on another R package located on GitHub

r github package

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Error in installation a R package

r installation package

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