What Causes the Last Time You Opened It Caused a Serious Error in Excel?

This frustrating bug can be caused by various unexpected reasons and lead to significant inconvenience. Here are the most common causes:

1. Corruption in the Excel file
2. Outdated Excel software versions
3. Due to corrupted or faulty add-ins
4. Malware or virus infections
5. Program to quit unexpectedly
6. Corrupted Office Suite
7. Insufficient system resources

Is It Essential to Fix Excel Serious Error Immediately?

Yes, it is essential to fix Excel’s serious error immediately because it may restrict you from opening or accessing your crucial workbook data and can lead to severe data loss. So, consider solving this warning message promptly to access your spreadsheet data and ensure a smooth workflow.

Quick Fixes:

1. Reboot your PC
2. Disable Faulty Add-Ins
3. Repair Corrupt or Damaged Excel Workbook
4. By Updating Excel
5. Open Excel in a Safe Mode
6. Check the Memory Usage
7. Copy Excel Workbook Data to a New Workbook
8. Repair MS Office Application
9. Contact Microsoft Support Team

Method 1- Reboot your PC

Restarting your computer can indeed be a useful solution for various problems including MS Excel serious error. When you restart your computer, it clears the system’s memory & may solve the temporary malfunctions that could be triggering this error.

Method 2- Disable Faulty Add-Ins

In several community websites, many users have reported that they received the last time you opened it caused a serious error due to faulty Excel add-ins and hence, fixed by disabling them. So, you should also try to diagnose and disable the faulty add-ins in Excel to overcome this situation.

Follow the steps to turn OFF the Excel add-ins:

1. Open the Excel application, and click on Options >> Add-ins.
2. Under the Excel options window, choose the COM Add-ins from the drop-down >> click on Go button.
3. Now, deselect all the checkboxes >> click OK.
4. Restart your PC to check for the problem.

Method 3- Repair Corrupt or Damaged Excel Workbook

1. Launch the Excel application >> click on Open.
2. Go to the folder to select the corrupt workbook.
3. In an Open dialog box, choose the faulty XLS/XLSX file.
4. Next, click an arrow next to Open button >> tap on Open and Repair.
5. At last, click on “Repair” to recover as much of the workbook data.

Method 4- Fix The Last Time You Opened It Caused a Serious Error by Updating Excel

1. Open Excel >> navigate to the “Account” option.
2. Then, click on the “Update Options.”
3. Now, click on the “Update Now” option to install the latest updates.

Method 5- Open Excel in a Safe Mode

The next method you can try to deal with Microsoft Excel the last time you opened it caused a serious error is opening the Excel file in a safe mode. However, this will help to easily detect any problematic add-ins that are generating this error & later disable them.

Method 6- Check the Memory Usage

You can even check & close the unnecessary applications running in the system’s background to free up some memory. For this, follow the steps below:

To do so, follow these steps:

1. Press the CTRL + ALT + DEL keys together on the keyboard >> click Task Manager.
2. Next, go to the Processes tab & look for any unnecessary processes.
3. Simply right-click on a process no longer needed>> choose End Task.
4. Relaunch Excel to see if the error is fixed.

Method 7- Copy Excel Workbook Data to a New Workbook

Numerous users have confirmed that they are able to fix the last time you opened it caused a serious error Excel by copying data from the affected XLSX file to a new workbook.

Here are the steps to be followed:

1. Find the location where the affected document is saved.
2. Then, right-click on it to choose Properties.
3. Under Properties window, click on ‘Read Only’ option in the General.
4. After this, try to open the file in ‘Read Only’ mode.
5. Now, if it opens, then copy all its data and paste it into a new file.
6. Finally, save the file with another name.

Method 8- Repair MS Office Application

As already mentioned in the causes section, corruption in the MS Office suite can even lead to this peculiar error. To solve this, consider repairing the Microsoft Office application by following the instructions below:

1. Go to the Start menu.
2. Type Apps and Features or Installed apps in a search bar, then choose the result.
3. Locate and select the MS Office entire package >> select Modify.
4. In the How would you like to repair your Office Programs window, click on Quick Repair.
5. Now, click the Repair button and follow the onscreen instructions until the process ends.