I am facing this issue and can't get a work around, did you solve it?

No... not really... have you tried putting the R executables in your app folder? It might work for you...

Nope, I, i am not sure where i should exactly place that, is it on the bin folder??

I was looking at this website; https://rdrr.io/cran/RInno/man/create_app.html.
the default R version is the R version you're using, i.e
paste0(">=", R.version$major, '.', R.version$minor)

funny enough using
include_R = TRUE,
R_version="2.2.1")

knows that the version is not supported

Error: R_version (2.2.1) <= 3.0.2 is not supported.

I don't know if anyone answered this but I got a fix by doing this:

trace(get_R,edit=T)

Then you should change this part of the code:

latest_R_version <- readLines("https://cran.rstudio.com/bin/windows/base/", warn = F) %>% stringr::str_extract("[1-3]\\.[0-9] \\.[0-9] ") %>% stats::na.omit() %>% unique()

It looks at cran for the latest version, but it only accounts for versions between 1 and 3 (the latest is R-4.0.1 for Windows). Therefore, just change 3 for 4, save it and you should be OK.

This solution is temporary. Expect doing this everytime you restart a R Session or just change it from the source version of the package.

Since it is a simple solution, maybe RInno's maintainers had already fixed it in the most up-to-date version.

super!! i spend my whole weekend searching the get_R file from the R inno package files.
you saved me

I was running into the same problem using RInno_1.0.1 from Cran (e.g. install.packages(RInno)) . I had to replace the 3 with the 4 in the trace(RInno::get_R,edit=T) but also in the trace(RInno::code_section,edit=T) to succesfully compile the app.

Via roman-tremmel. I created a fork that does this so I don't need to keep editing it. Found at Git hub "brandonerose/RInno"

I am facing the same error with create_app with argument include_R = TRUE, R_version = "4.0.0"

Error in if (latest_R_version == R_version) { : 
  argument is of length zero

However when I change the 3 to 4 in the latest_R_version in trace(RInno::get_R,edit=T) and trace(RInno::code_section,edit=T)

I am still getting an error

Error in if (latest_R_version == R_version) { : 
  the condition has length > 1

How to fix this?

I am still getting an error

Error in if (latest_R_version == R_version) { : 
  the condition has length > 1

How to fix this?

latest_R_version is a vector containing several values, which explains the error in the condition.
To fix this, add the index of the first value in the condition (with trace(RInno::get_R,edit=T)) :
if (latest_R_version[1] == R_version)
instead of :
if (latest_R_version == R_version)

This works for me, but the problems come later. Can you tell me if you succeed to generate a stand-alone application?