I can not enter the book value on the T5008 form. When I put the value in and close the form the book value goes to 0.00

[TurboTaxKim]

It may appear the number you are entering in Box 20 is not staying on your T5008 entry when you are looking at the T5008 Summary page. What you will see here are the amounts from Box 21 of the T5008 slip only. The actual capital gain/loss is not seen on this page.

After completing all your entries, if you have a Capital Gain, you will see it on Line 127 of the Detailed Tax Summary. Capital Losses are not seen on the current year's tax return. 

You can also see these entries after you pay for your return (even the Free version must go through the payment process) on the PDF view of the T1 General.

[TurboTaxKim]

If the book value in Box 20 of your T5008 slip is still causing an issue, please contact our Customer Support team. https://turbotax.community.intuit.ca/replies/3152013