Hi Julian

If a user is trying to amend a Quotation that has the status of 'Posted', they need to have the appropriate capabilities (Edit Posted Customer Quotation Custom fields and/or Edit Posted Customer Quotations).  However, this doesn't apply to Opportunities and in addition, as the System Administrator on your account you should automatically have these capabilities.

When you click Add line item, you should see a screen similar to the one shown below (click to enlarge).

If you've entered Products into your Product Book you can start typing the product code into the product field (which will pull through any description and pricing information you've added at the product level).  Alternatively, you can just free type a Line Description, enter a Quantity and populate the pricing and any other fields you want to complete.

Once you've added all the information, click Update to add those changes to the Opportunity/Quotation.

Hopefully this helps but if you still have any problems with this, please describe the steps you're taking and, ideally, upload a screenshot. Thanks.

Hi Julian

This issue has been identified as being a browser issue - are you using IE8?  Please try using Google Chrome or Safari. If the problem still exists in a different browser, please let us know.