The application failed to start - Error in value[[3L]](cond) : RStudio not running

i deployed my app on I used deployApp() for this purpose and the deployment process was successful but when I go to my app url I get the error message below. I don't really understand what the problem is.
My app works when executed locally.
I made sure that I have installed the latest version of all the packages that are used and I am using the latest version of RStudio.
The script is named "app.R" and the data it uses is uploaded as well.

Does someone have an idea? Thanks in advance for your help!

> # An error has occurred
> The application failed to start (exited with code 1).
> `Attache Paket: ‘dplyr’
> The following objects are masked from ‘package:stats’:
>     filter, lag
> The following objects are masked from ‘package:base’:
>     intersect, setdiff, setequal, union
> Error in value[[3L]](cond) : RStudio not running
> Calls: local ... tryCatch -> tryCatchList -> tryCatchOne -> <Anonymous>
> Execution halted

The log files looks like this:

> 2018-09-30T11:38:39.525608+00:00 shinyapps[478517]: Server version: 1.6.8-6
> 2018-09-30T11:38:39.525611+00:00 shinyapps[478517]: LANG: de_DE.UTF-8
> 2018-09-30T11:38:39.525646+00:00 shinyapps[478517]: R version: 3.4.4
> 2018-09-30T11:38:39.525647+00:00 shinyapps[478517]: shiny version: 1.1.0
> 2018-09-30T11:38:39.525649+00:00 shinyapps[478517]: httpuv version: 1.4.5
> 2018-09-30T11:38:39.525650+00:00 shinyapps[478517]: rmarkdown version: NA
> 2018-09-30T11:38:39.525650+00:00 shinyapps[478517]: knitr version: NA
> 2018-09-30T11:38:39.525651+00:00 shinyapps[478517]: jsonlite version: 1.5
> 2018-09-30T11:38:39.525652+00:00 shinyapps[478517]: RJSONIO version: NA
> 2018-09-30T11:38:39.525658+00:00 shinyapps[478517]: htmltools version: 0.3.6
> 2018-09-30T11:38:39.525750+00:00 shinyapps[478517]: Using pandoc at /opt/connect/ext/pandoc2
> 2018-09-30T11:38:39.665426+00:00 shinyapps[478517]: Using jsonlite for JSON processing
> 2018-09-30T11:38:39.761737+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:39.761742+00:00 shinyapps[478517]: Starting R with process ID: '84'
> 2018-09-30T11:38:40.014435+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.016423+00:00 shinyapps[478517]: The following objects are masked from ‘package:base’:
> 2018-09-30T11:38:40.015246+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.016424+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.016426+00:00 shinyapps[478517]:     intersect, setdiff, setequal, union
> 2018-09-30T11:38:40.014430+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.105901+00:00 shinyapps[478517]: Error in value[[3L]](cond) : RStudio not running
> 2018-09-30T11:38:40.014433+00:00 shinyapps[478517]: Attache Paket: ‘dplyr’
> 2018-09-30T11:38:40.015247+00:00 shinyapps[478517]:     filter, lag
> 2018-09-30T11:38:40.015244+00:00 shinyapps[478517]: The following objects are masked from ‘package:stats’:
> 2018-09-30T11:38:40.015247+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.016426+00:00 shinyapps[478517]: 
> 2018-09-30T11:38:40.105904+00:00 shinyapps[478517]: Calls: local ... tryCatch -> tryCatchList -> tryCatchOne -> <Anonymous>
> 2018-09-30T11:38:40.105905+00:00 shinyapps[478517]: Execution halted

Looks like you might have some code that is checking if the RStudio IDE is running, or otherwise attempting to make a call to it.

Thank you.
I fixed the problem. It was a bit stupid. In my R code i used the following command to set the workspace to the folder where the script is:

This command obviously needs RStudio to run. After deleting this line of code, my app work online.