Understanding the Memory Limit
One of the most frustrating errors in Excel is the "Out of Memory" alert. This typically happens because of the limitations in the 32-bit version of Excel, which can only address 2GB of virtual memory process space.
Step 1: Check Your Excel Version
Go to File > Account > About Excel. If you are running 32-bit Excel on a 64-bit Windows machine, you are severely limiting your potential. Upgrading to 64-bit Excel allows the application to use all available system RAM.
Step 2: Disable Hardware Graphics Acceleration
Sometimes, the GPU rendering causes memory leaks. Go to File > Options > Advanced > Display and check "Disable hardware graphics acceleration".
Step 3: Break Links and External References
If your workbook links to many other closed workbooks, memory usage spikes. Try to value-paste data that doesn't need to be live.
Step 4: Optimize Formulas
Volatile functions like INDIRECT(), OFFSET(), and TODAY() recalculate every time any cell is changed. Replace them with INDEX/MATCH combinations where possible.
Step 5: Reduce File Size
Save your file as a binary workbook (.xlsb). This format is faster and smaller than the standard XML-based .xlsx format.