Saving a global variable to a file

I have several text boxes joining text contents to a global TimeString and after saving this global variable to a file timeString.txt. It is not working, perhaps the usage of the get global TimeString is not correct.
blockSave

Your file is saved to your SD card already. It has a slash at the beginning.

What is not working?

The timeString.txt file is created in home/Internal shared storage/timeString.txt but when I try to open it I am receiving the message "The file format is not supported".
Meanwhile, I have other text files being possible to open with the browser.

To open it with what? Try to read the file with the File component.
And show your blocks.

I am using a windows notepad to open it.
But after doing the part related to read a file and running it everything is perfect.
This is the block reading file.

So what's the problem?