If you want to change/increase assignment submission file size then, follow the steps below;
Part 1
Step 1 - Click the ⚙ gear icon on the top-right of the page and select edit settings
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Step 2 - Click Edit on the assignment or activity that you want to amend then click on Edit settings from the drop-down list.
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Part 2
Step 1 - Scroll down until Submission types and click on it.
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Step 2 - Click on the Maximum submission size drop-down to change the file size to be uploaded in this activity or assignment.
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If you want to increase the maximum upload size limit which is currently by default 250 MB then you can change the setting in the course material upload setting, click here to know more.
Step 3 - Click Save and return to course or Save and display.
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