Do you have slow workbooks due to size bloat? Give us a try at speeding up.

Prash_MSFT, I am the developer and eCommerce manager for my company. The key Excel application I develop here is a collection of 3 workbooks - 2 of which over 100MB in size (too large for MS-365 for the Web). WB1 links to WB2 and WB3 to import data tables. (WB2 was split off from WB1 to reduce its size from over 200MB and to segregate data tabs from "working" tabs.)

Excel fails to open WB1 AT LEAST once per week, finding it corrupted. I am puzzled by this because I am the only person to save it and it was in working order each time. In the last few instances, I reopened the file after saving and exiting Excel to verify it was structurally sound. It opened flawlessly, yet the next day it was unable to be opened or opened without recognizing and running embedded VBA scripts, including an "On Open" subroutine that should have, for example, set calculations to Manual and activated a designated tab. When that happens I sometimes cannot view the VBA at all; sometimes I can view it but cannot save changes, nor remove the module and import a backup copy. My only recourse is to retreat to a prior version and fervently hope that I fully documented formula and VBA changes applied subsequent to that version.

At first, I thought the cause was an odd interaction between Excel and SharePoint. I removed SharePoint from the equation by moving the workbook to a local drive (requiring manual saves and archival copies) but that made no difference.

I opened a case with Support and was told, "This is a development issue. We don't do that. Hire a consultant." That is not what I call support.

There is so much proprietary data whose content defines how it is processed and presented that obfuscation would be a monumental effort, if achievable at all. I am, however, available for a remote session with you to demonstrate the project and examine a damaged version which I have retained for that purpose.

I am turning to you because, frankly, no one else at Microsoft is willing to assist and your blog post is likely highly relevant to our situation.

I look forward to hearing back from you,

Marc