How about you try this AFTER installing and converting to Quicken Subscription HB&R ...
If you're an active trader and your current investment account has many transactions pertaining to sold securities you may want to consider this:
Archive Investment Transactions
For about a year now, a new function has been available in Quicken, Archive Transactions. It will split your investment account register into two parts, leaving only those securities' transactions where you currently hold >0 shares in the active register. The rest is moved to a new Archive register within the current data file.
Having less transactions in your active register might improve performance.
Please read and carefully follow instructions here: https://www.quicken.com/support/how-archive-investment-transactions Eventually, after a couple of years, you might consider splitting your data file in two, with all the archived investment transactions in the old file and none remaining in the active file.