I am trying to run linear mixed effects models with package lme4 in R. I have the most recent versions of R & RStudio, have updated the lme4 package, and continue to get the error that package ‘Matrix’ required by ‘lme4’ could not be found. I am not running into this problem on my personal computer after updating R & RStudio so I’m not quite sure what to do. Any help would be greatly appreciated– thanks in advance!

I am trying to run a multi-level model using the lmer function from the lme4 package but when I try and run the model, I get the following error: