when I try to open a document there is a message preventing me

That message usually means Word itself is failing to start or load correctly, not that the document is necessarily the problem.

Common causes supported here are:

• Office is not fully up to date.
• A Word add-in is causing Word to crash.
• Word may work only in Safe Mode, which points to an add-in issue.
• If the problem happens only with one file, the document may be damaged.

A practical troubleshooting path is:

1. Update Office
   • Open any Office app.
   • Go to File > Account.
   • Under Product Information, select Update Options > Update Now.
2. Start Word in Safe Mode
   • Open Run.
   • Type winword /safe and press Enter.
   • If Word opens in Safe Mode, the issue is likely caused by an add-in.
3. Disable add-ins one at a time
   • In Word, go to File > Options > Add-Ins.
   • In the Manage list, choose Word Add-ins or COM Add-ins, then select Go.
   • Clear one add-in, select OK, and restart Word normally.
   • If Word starts, the disabled add-in is the cause.
4. Run an Online Repair of Office
   • If the built-in Repair now prompt does not fix it, use Online Repair instead.
   • In Windows, go to Start > Settings > System > Apps > Installed apps.
   • Find Microsoft Office, select the three-dot menu, choose Modify, then choose Online Repair and Repair.
   • This is more thorough than the in-app repair prompt.
5. If the problem is only with one document
   • In Word, go to File > Open > Browse.
   • Select the file.
   • Select the arrow next to Open, then choose Open and Repair.

If Word still fails even in Safe Mode, the documented next step is to repair Office.

• I get a "stopped working" error when I start Office applications on my PC
• Open a document after a file corruption error
• How to fix MS Word has run into an error that is preventing from working properly. Word will need to be closed as a result. - Microsoft Q&A