---
title: "“Unable to set the installed property of the add-in class” error message"
description: "If Excel 2007 crashes while running a RealData product, you may find that whenever you open the same RealData product thereafter, you see this message: *Runtime error 1004: Unable to set the installed property of the add-in class.* The cause…"
url: "https://www.realdata.com/docs/unable-to-set-the-installed-property-of-the-add-in-class-error-message/"
updated: "2024-06-06"
category: General
---

# “Unable to set the installed property of the add-in class” error message

If Excel 2007 crashes while running a RealData product, you may find that whenever you open the same RealData product thereafter, you see this message:

*Runtime error 1004: Unable to set the installed property of the add-in class.*

The cause of this problem is unknown, but you can work around it as follows:

After seeing the above message, while still in the product, select "Excel Options" from the Office Menu (circle at top left) or File > Options. Select "Add-Ins", then find "Manage: Excel Add-Ins", and click "Go...".

Find the appropriate add-in for the product you are running:

for REIA Standard Edition v14: Realdata-Reia14A
 for REIA Standard Edition v15: Realdata-Reia15
 for REIA Standard Edition v16: Realdata-Reia16
 for REIA Standard Edition v17: Realdata-Reia17
 for Comparison Analysis: Realdata-Ca1A
 for Portfolio Analysis: Realdata-Pa1A
 for REIA Lite Edition: Realdata-Lite11A
 for REIA UltraLite Edition: Realdata-Ul2A
 for REIA Express Edition v2: Realdata-Ee2
 for C/I Development v5: Realdata-Cid5A
 for C/I Development v6: Realdata-Cid6
 for On Schedule v5: Realdata-Os5
 for Comparative Lease Analysis v2: Realdata-Cla2A
 for Comparative Lease Analysis v3: Realdata-Cla3
 for Personal Financial Statement: Realdata-Pfs4
 for 1031 Exchange Analysis: Realdata-1031

Click the checkbox for that add-in, and click OK. This should resolve the problem.