How to protect/lock an Excel template being overwritten with password?

To protect or lock an Excel template being overwritten with a password, we can apply the Protect Sheet feature in Excel. And you can do as following:
Step 1: Create a workbook, enter data and format it. Then select the cells you allow users to edit in future.

Note: You can select multiple cells with holding the Ctrl key and selecting multiple range or single cell one by one.

Step 2: Click the Anchor in the Alignment group on the Home tab, then go to the Protection tab of Format Cells dialog box, uncheck the Locked option, and click the OK button.

Step 3: Go ahead to click the Review > Protect Sheet.

Step 4: In the opening Protect Sheet dialog box, keep checking the option of Protect worksheet and contents of locked cells, next enter a password into the Password to unprotect sheet box, and click the OK button.

Step 5: Reenter the password into the coming Confirm Password dialog box, and click the OK button.

Step 6: Click the File > Save > Computer > Computer > Browse in Excel 2013, or click the File / Office Button > Save in Excel 2007 and 2010.

Step 7: In the coming Save As dialog box, enter a name for this workbook in the File name box, and click the Save as type box and select Excel Template (*.xltx) from drop down list, at last click the Save button.

The protection made by this method does not affect other users to apply this Excel template at all.

There is an alternative method to protect or lock an Excel template with configuring the save options and setting open password and modify password. And you can do as following:

Step 1: Create a workbook, enter you data and format it as you need.

Step 2: Click the File > Save > Computer > Computer > Browse in Excel 2013, or click the File / Office Button > Save in Excel 2007 and 2010.

Step 3: In the coming Save As dialog box,

(1) Enter a name for this workbook in the File name box;

(2) Click the Save as type box and select Excel Template (*.xltx) from drop down list;

(3) Click the Tools > General Options.

Step 4: In the General Options dialog box, enter password:

1. To set open password, please enter a password into the Password to Open box;
2. To set modify password, please enter a password into the Password to modify box;
3. You can set both open password and modify password together.

Step 5: Click the OK button in the General Options dialog box. Then the Confirm Password dialog box opens, reenter your open password or modify password into this dialog box, and click the OK button.

Note: If you set both open password and modify password together, in the first Confirm Password dialog box enter your open password and click the OK button; and in the second Confirm Password dialog box enter your modify password and click the OK button.

Step 6: Click the Save button in the Save As dialog box.

Notes:

(1) If you protect an Excel template by modify password, it won’t affect other users applying this Excel template.

(2) If you protect an Excel template by open password, it will ask for entering password when other users apply this Excel template.

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