Hi @Aysenur Atlac (IT-WGUARD),
The SharePoint Online indexer does not support indexing .ASPX site content due to specific limitations set by the indexing feature. While .ASPX files are indeed a type of web page format, the indexer is designed to extract content from certain document formats that are more structured and suitable for content indexing. HTML is supported because it is a widely used format for web content that can be easily parsed and indexed, while .ASPX files often contain dynamic content and server-side scripts that may not be suitable for indexing in the same way. The limitations are in place to ensure that the indexing process is efficient and effective, focusing on document formats that provide clear and static content for searchability.
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