Placeholder and other entries can be viewed in the security detail view. PLaceholder entries are not visible in the register where most transactions can be viewed, edited and deleted. I have a similar problem with placeholder entries that were entered when I attempted to adjust share balances. Now the security is a mess and everything I have done so far has made things worse. I am holding off attempting to delete the entire investment account and re-entering (if this will work?) Deleting the individual security is not allowed unless all entries are deleted first.
I agree: how do we delete placeholder entries in Quicken 2018??
One further idea: if for some reason the Placeholders are still not displayed in your transaction list, you can go to Reports/Banking/Transaction to show the Banking Transaction report. Adjust the date range if necessary and group by account. The Placeholders will have *Placeholder in the Num column. Select the one(s) you want to delete and right-click to delete. For some reason Quicken doesn't let you delete transactions from the Investment Transaction report.As always before anything like this, do a backup first so you can revert if something goes awry.