SharePoint Server 2019 Problem uploading and downloading documents with "form " in file name

[goldf35]

Just wondering if anyone has seen this issue using SharePoint Server 2019.  Users are getting an error "Sorry, there was a problem uploading this file.  Please try again." when uploading documents with the word "form " as part of the filename to a document library.  It's actually failing on any file name ending in "form ", so "transform ", "approval form - part I", "Form 111", etc.  If I rename to "approval form-part I" (no spaces), then it will work.  As long as the word "form" is not followed by a space character, it works.  I'm sure "form" is not a reserved word but see nothing in the ULS logs to indicate what the error could be from.  This happens on both .doc, .docx and PDF files.  Does anyone know what may be causing this?  I just recently began work on this site and know that it was migrated from SharePoint 2016 to 2019 recently.  Also, if I switch to "classic view" on the document library, I can upload it, but not in modern view.

Thanks for any input.  Thao

[#2]

@goldf35 

Try this

Microsoft Office Upload Center
Introduction The Microsoft Office Upload Center lets you keep track of how uploads are progressing. When you upload a file to a web server (e.g. TIMS), Microsoft saves that file locally to the Office Document Cache before it starts the upload. This icon
indicates that the file has changes that have failed to upload. Errors will sometimes occur during the upload in which case the Document Cache needs to be “reset” before attempting to upload the revised document.
Steps Refer to images starting on page 2 as needed.


Step Action 1 Select Start Menu, then type: Upload Center 2 Select Office 2016 Upload Center (or 2013 Office Upload Center, if the 2016 version is not available) 3 Select Settings 4 Under Cache Settings, click Delete cached files button 5 Before clicking on the OK button, click on the box next to Delete files from the office Document Cache when they are closed

Additional Information
For more information about the Microsoft Office Upload Center, please refer to the content for Microsoft Office Upload Center at https://support.office.com.

[#3]

@gjoinerThank you, I tried this but it didn't make a difference.  I can upload/download the files as long as I rename it to not have a space after the word "form", it just always fail on any file with "form " in the name.  It seems to not properly process the urls built for the link when any of the documents have a pattern of "*form " in the file name.  For example, this download link for "Form 111.doc" does not work:

https://mydomainname.com/_layouts/15/download.aspx?SourceUrl=%2FFormsTemplates%2FForm%20111%2Edoc

But this link for "Formb 111.doc" does work:

https://mydomainname.com/_layouts/15/download.aspx?SourceUrl=%2FFormsTemplates%2FFormb%20111%2Edoc

[#4 · Accepted solution]

@goldf35We found the cause so I'm updating in case anyone runs into this obscure problem.  We're using a KEMP load balancer and a setting in it was causing this issue.  When testing bypassing the load balancer, all was working fine which led us to realize that KEMP was the issue.  Our forms are now uploading successfully without the naming restriction.  KEMP developers are looking into fixing this.