Visual Basic for Applications Reference
Bad file name or number (Error 52)
See Also Specifics
An error occurred trying to access the specified file. This error has the following causes and solutions:
A statement refers to a file with a file number or file name that is:
Not specified in the Open statement or was specified in an Open statement, but has since been closed.
Specify the file name in an Open statement. Note that if you invoked the Close statement without argument, you may have inadvertently closed all currently open files, invalidating all file numbers.
Out of the range of file numbers (1 511).
If your code is generating file numbers algorithmically, make sure the numbers are valid.
There is an invalid name or number.
File names must conform to operating system conventions as well as Basic file-naming conventions. In Microsoft Windows, use the following conventions for naming files and directories:
The name of a file or directory can have two parts: a name and an optional extension. The two parts are separated by a period, for example, myfile.new.
The name can contain up to 255 characters.
The name must start with either a letter or number. It can contain any uppercase or lowercase characters (file names aren't case-sensitive) except the following characters: quotation mark ("), apostrophe ('), slash (/), backslash (\), colon (:), and vertical bar (|).
The name can contain spaces.
The following names are reserved and can't be used for files or directories: CON, AUX, COM1, COM2, COM3, COM4, LPT1, LPT2, LPT3, PRN, and NUL. For example, if you try to name a file PRN in an Open statement, the default printer will simply become the destination for Print # and Write # statements directed to the file number specified in the Open statement.
The following are examples of valid Microsoft Windows file names:
LETTER.DOC My Memo.Txt BUDGET.92 12345678.901 Second Try.Rpt
For additional information, select the item in question and press F1.