Delphi's online help documentation seems to miss the run-time error codes. I usually looked them up in my old Borland Pascal for Windows help file - now they are here for fast access:
1 Invalid function number
2 File not found
3 Path not found
4 Too many open files
5 File access denied
6 Invalid file handle
12 Invalid file access code
15 Invalid drive number
16 Cannot remove current directory
17 Cannot rename across drives
100 Disk read error
101 Disk write error
102 File not assigned
103 File not open
104 File not open for input
105 File not open for output
106 Invalid numeric format
200 Division by zero
201 Range check error
202 Stack overflow error
203 Heap overflow error
204 Invalid pointer operation
205 Floating point overflow
206 Floating point underflow
207 Invalid floating point operation
210 Object not initialized
211 Call to abstract method
212 Stream registration error
213 Collection index out of range
214 Collection overflow error
215 Arithmetic overflow error
216 General protection fault

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