Unable to fetch app definition. Error: because it is not in .xlsx format

From time to time I am getting this error. My app is functioning normally but sometimes I am getting this error message. Every time I should open and save the backend file. In the editor, there is not an error shown.

I see your data source is probably excel files saved in the One Drive. As far as I know, whenever the file remain open, the appsheet app is not working. Meaning it should be default behavior.

That is one of the reason I avoid to use excel, but stay with Google Sheet, which is most seamless in terms of app operation.


Thank you for your time,

Yes it is an excel file, and it is on Google Drive, but I don’t open it so often. When I open the file I close and check the app is working.
This happens sometimes. Support directed me to this article but it is not related to this issue.

When I tested Excel before with appsheet (some years back), I remember I observed same odd behavior, but not sure why it happens, but at least I learned Appsheet + Excel on cloud combination is not stable. All in all, I never use Excel as data source for Appsheet alone.

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I agree with @tsuji_koichi’s sentiment that Google Sheets is a better choice than Excel as a data store for your app. Excel is definitely limited, in that you cannot access the spreadsheet both via Excel and with the app at the same time. If the spreadsheet is open in Excel, the app cannot use the spreadsheet. Google Sheets does not have this limitation.


Odd but if the Excel is under share-point, the app works but with some kinda delay. For example; if you add a column to the table and regenerate the column structure, the operation cannot sometimes fetch the change. Also with the Deck View, sometimes the images might not appear. But over the haul, app works. Tested for a couple of days.


Yes, all in all, I would say Appsheet + Excel pair is unstable…
Excel, in history, came from on-premise, and trying to reform or adjust themself to work “on cloud”, while Google sheet has been cloud solution by nature…
For instance, some of important features to manage the back-end service, such as “query” function is working on excel if the file is opened on premise, but it wont work on cloud, Excel Online, or Excel file sits on Cloud.

Now the solutions moves to “Cloud”, in essense, the solutions which is not fit to cloud based solution is not really match with Appsheet, which is purely “cloud” solution, in my opinion. As a result, for me, I made it a rule not to use Excel when it comes to Appsheet.

All in my opinion.


Back to the original subject of this post, but sorry for my own opinion to share.

the problem with Excel file as data source for Apsheet, which we could say “problem” but Appsheet should not be blamed, as I see it is Excel problem rather than Appsheet where appsheet dev team should have no control over it, and Appsheet should not be criticiszed.

The typical problem we see on Excel as data source to Appsheet. While the Excel file opened, then Appsheet wont work. This is pure Excel: ish problem, as the Excel file is generally not “sharable”. Once the file is opened, the “session” is deemed to be going on, where no other person can interact with the file. Excel should have shareable option, but as I said, this is Option. Primarily, Excel file is not designed to share and work together with other user at the same time…

This single story tells now the Excels works, and why Excel would not work friendly with Appsheet unfortunately. We neeed to speak to MS in Seattle to solve this rather than asking to Appsheet dev.

Once again, out of my humble own opinion.


Some of my existing clients (use Appsheet) originally share the information over the Excel Online, who found it is bullshit. (Im sorry for my dirty words)

The file grows, it naturally gets heavy.

Even just open the file, it takes forever.

That s one of the reasons people forget about Excel (or online) to share the information and data, and moves to other solutions like Appsheet.

winds are following Appsheet in general.


To defend (in very light terms because I also very strongly agree excel is not even moderately ideal for appsheet let alone other uses) excel, some users just refuse to use things other than excel and when these users are at the high levels of your company it can be extremely difficult/impossible to get them to move away from it. Case and point, we have Appsheet and Tableau as our current data consumption platform that is where we do 95% of our reporting but we still have to bend to some users wanting an excel sheet that they can use because they’ve spent the life of excel doing things in it. Sometimes an old dog knows too many old tricks.

Data base, source is just a source.
It does not matter where it sits.

As appsheet creator or app developper we do not want to let the users to touch opon, as their direct interaction to the data base may easily break the Apps (up…).

For me, either Excel or Google Spreadsheet, wont give much of differences, but as I stated, Google Spreadsheet is much easier to interact.

If you need to “present” Appsheet data “On the excel spreadsheet”, then probably I will set the data base of Appsheet app to MS SQL.

Then on Excel file, on the data pane, I set the extract data from MS SQL to present to the user who wish to access to data being captured by Appsheet app.

They can play with data on Excel, but whatever bullshit they do on that data, it wont affect Appsheet app operation.

Could you please explain how to accomplish this or refer an article for that if it exists.
Thank you.

this is not a subject related to Appsheet, but it is how to deal with Excel. Search on Google with words like “Excel import/extract data from SQL” something like that, then you will see bunch of site which guide you well.

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