This is related to your Upload Bandwidth. This may happen if you are trying to save a project Online but you have a Low Upload Bandwidth. Explaindio Elements will try to upload your project to our online storage but if it's taking too long due to your low upload speed, after a time the software will release the connection and stop trying returning you this error message: Error Uploading Project

Once you Click OK it keeps on Saving forever.

If you encounter such error, please follow these steps:

Step 1: Click X on the top right corner to close Explaindio Elements

Step 2:Unchecked Save Also Online and keep Save "elements_zip" archive checked. Click YES to save the project locally on your computer Hard Drive. 

You will be able to save your project on your local computer. Later on you can open it from your local computer by clicking Open Project, then Browse Disk.  

Now, please follow the below troubleshooting steps to confirm if it's related to your Upload Bandwidth or not:

1. Check your Internet connection and make sure you are correctly connected to Internet. Also, make sure your connection is Stable.

2. Consider Rebooting your Modem/Router and then give it a one more try.

3. If you still encounter the same issue, create a small test project with 1 or 2 small slides. Then try saving it online. 

4. If you were able to upload that small test project online, it's now surely an upload bandwidth issue.

5. So, in this case, you may keep saving your projects on your local computer and always make sure you unchecked the Save Also Online option. 

6. Also, if you still want to save your projects online, consider increasing your upload bandwidth and try.